56639904 has 48 divisors (see below), whose sum is σ = 149506560. Its totient is φ = 18775040.

The previous prime is 56639879. The next prime is 56639923. The reversal of 56639904 is 40993665.

It is a tau number, because it is divible by the number of its divisors (48).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16792 + ... + 19880.

It is an arithmetic number, because the mean of its divisors is an integer number (3114720).

Almost surely, 2^56639904 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 56639904, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (74753280).

56639904 is an abundant number, since it is smaller than the sum of its proper divisors (92866656).

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

56639904 is a wasteful number, since it uses less digits than its factorization.

56639904 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3293 (or 3285 counting only the distinct ones).

The product of its (nonzero) digits is 174960, while the sum is 42.

The square root of 56639904 is about 7525.9487109600. The cubic root of 56639904 is about 384.0379736752.

It can be divided in two parts, 566 and 39904, that added together give a triangular number (40470 = T₂₈₄).

The spelling of 56639904 in words is "fifty-six million, six hundred thirty-nine thousand, nine hundred four".