78404928 has 56 divisors (see below), whose sum is σ = 237085632. Its totient is φ = 22401024.

The previous prime is 78404903. The next prime is 78404957. The reversal of 78404928 is 82940487.

It is a tau number, because it is divible by the number of its divisors (56).

It is a super-2 number, since 2×78404928² = 12294665469370368, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a self number, because there is not a number n which added to its sum of digits gives 78404928.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 27825 + ... + 30512.

It is an arithmetic number, because the mean of its divisors is an integer number (4233672).

Almost surely, 2^78404928 is an apocalyptic number.

It is an amenable number.

78404928 is an abundant number, since it is smaller than the sum of its proper divisors (158680704).

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

78404928 is a wasteful number, since it uses less digits than its factorization.

78404928 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 58359 (or 58349 counting only the distinct ones).

The product of its (nonzero) digits is 129024, while the sum is 42.

The square root of 78404928 is about 8854.6557245327. The cubic root of 78404928 is about 428.0039595523.

The spelling of 78404928 in words is "seventy-eight million, four hundred four thousand, nine hundred twenty-eight".