638737056 has 96 divisors (see below), whose sum is σ = 1972615680. Its totient is φ = 200383488.

The previous prime is 638737037. The next prime is 638737067. The reversal of 638737056 is 650737836.

638737056 is a `hidden beast` number, since 638 + 7 + 3 + 7 + 0 + 5 + 6 = 666.

It is a tau number, because it is divible by the number of its divisors (96).

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 15 ways as a sum of consecutive naturals, for example, 7056 + ... + 36431.

It is an arithmetic number, because the mean of its divisors is an integer number (20548080).

Almost surely, 2^638737056 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 638737056, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (986307840).

638737056 is an abundant number, since it is smaller than the sum of its proper divisors (1333878624).

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

638737056 is a wasteful number, since it uses less digits than its factorization.

638737056 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43523 (or 43509 counting only the distinct ones).

The product of its (nonzero) digits is 635040, while the sum is 45.

The square root of 638737056 is about 25273.2478324413. The cubic root of 638737056 is about 861.2066422393.

The spelling of 638737056 in words is "six hundred thirty-eight million, seven hundred thirty-seven thousand, fifty-six".