77904 has 30 divisors (see below), whose sum is σ = 218426. Its totient is φ = 25920.

The previous prime is 77899. The next prime is 77929. The reversal of 77904 is 40977.

It can be written as a sum of positive squares in only one way, i.e., 63504 + 14400 = 252^2 + 120^2 .

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 127 + ... + 414.

2⁷⁷⁹⁰⁴ is an apocalyptic number.

It is an amenable number.

77904 is an abundant number, since it is smaller than the sum of its proper divisors (140522).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

77904 is a wasteful number, since it uses less digits than its factorization.

77904 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 555 (or 546 counting only the distinct ones).

The product of its (nonzero) digits is 1764, while the sum is 27.

The square root of 77904 is about 279.1128803907. The cubic root of 77904 is about 42.7090507646.

Subtracting from 77904 its sum of digits (27), we obtain a palindrome (77877).

The spelling of 77904 in words is "seventy-seven thousand, nine hundred four".