In number theory, a happy number is a number which eventually reaches 1 when the number is replaced by the sum of the square of each digit. For instance...

palindromic number in bases 9 (779), 13 (5513) and 34 (2234). 70 is the thirteenth happy number in decimal, where 7 is the first such number greater than...

number, number of partitions of 38 into nonprime parts 806 = 2 × 13 × 31, sphenic number, nontotient, totient sum for first 51 integers, happy number...

triangular number, happy number 902 = 2 × 11 × 41, sphenic number, nontotient, Harshad number 903 = 3 × 7 × 43, sphenic number, 42nd triangular number, Schröder–Hipparchus...

centered heptagonal number, happy number, nice Friedman number since 736 = 7 + 36, Harshad number 737 = 11 × 67, palindromic number, blum integer. 738...

composite number, the second squarefree semiprime, the fourth triangular number, and a happy number. 10 is the smallest noncototient number. There are...

#1 Happy Family USA is an American adult animated sitcom created by Ramy Youssef and Pam Brady for Amazon Prime Video. It follows the Husseins, an Egyptian-American...

sequence. a happy number. palindromic in bases 10 (56510) and 11 (47411). 566 = 2 × 283. It is: nontotient. a happy number. a 2-Knödel number. 567 = 34...

prime exponent 608 = 25 × 19, Mertens function(608) = 0, nontotient, happy number, number of regions formed by drawing the line segments connecting any two...

prime, a Harshad number, a lucky prime, a happy number (happy prime), a safe prime (the only Mersenne safe prime), a Leyland number of the second kind...

primes (103 + 107 + 109), Smith number, cannot be represented as the sum of fewer than 19 fourth powers, happy number in base 10 320 = 26 × 5 = (25) ×...

numbers of Euler Fortunate number Happy number Harshad number Josephus problem Gambling Lottery Keno Weisstein, Eric W. "Lucky Number". mathworld.wolfram.com...

tree. a companion Pell number. a happy number. palindromic in bases 3 (100013), 9 (1019) and 40 (2240). The sixth magic number. Sloane, N. J. A. (ed.)...

One Is a Lonely Number (also known as Two Is a Happy Number) is a 1972 American drama film directed by Mel Stuart, and starring Trish Van Devere, Janet...

Christmas" of Western European tradition. The number 13 is a prime number, happy number and a lucky number. It is a twin prime with 11, as well as a cousin...

a Størmer number. Twenty-eight is a harmonic divisor number, a happy number, the 7th triangular number, a hexagonal number, a Leyland number of the second...

hypercomplex number system. 32 is the ninth 10-happy number, while 23 is the sixth. Their sum is 55, which is the tenth triangular number, while their...

the natural number following 43 and preceding 45. Forty-four is a repdigit and palindromic number in decimal. It is the tenth 10-happy number, and the fourth...

representations of the first two primes (2 and 3) and is itself also prime, and a happy number. The sum of the first nine primes up to 23 is a square: 2 + 3 + ⋯ + 23...

super-prime, happy prime 3023 – 84th Sophie Germain prime, 51st safe prime 3025 = 552, sum of the cubes of the first ten integers, centered octagonal number, dodecagonal...

"Happy Birthday to You", or simply "Happy Birthday", is a song traditionally sung to celebrate a person's birthday. According to the 1998 Guinness World...

natural number following 207 and preceding 209. 208 is a practical number, a tetranacci number, a rhombic matchstick number, a happy number, and a member...

square. As a decimal number, 68 is the last two-digit number to appear for the first time in the digits of pi. It is a happy number, meaning that repeatedly...

"Happy Happy" is a song recorded by South Korean girl group Twice. It is the group's fourth Japanese maxi single, featuring three other tracks. The song...

divisible by all of its digits, whose digit sum is also itself. It is a happy number in decimal, meaning that repeatedly summing the squares of its digits...

octagonal number 2211 – triangular number 2221 – super-prime, happy number 2222 – repdigit 2223 – Kaprekar number 2230 – sum of the totient function for...

(5545), 114 (22114), 229 (11229) a Harshad number in bases 2, 6, 10, 12, 23 (and 16 other bases). a happy number. a nontotient since there is no integer...

October 1993, when it peaked at number 42, it re-entered the chart twelve months later at number 40. "Happy Nation" reached number-one on the singles charts...

"Don't Worry, Be Happy" is a 1988 song by Bobby McFerrin, released as the first single from his album Simple Pleasures (1988). It was the first a cappella...

lucky prime and a happy number like its dual permutable prime in decimal (13). 31 is the number of regular polygons with an odd number of sides that are...