639354564 has 36 divisors (see below), whose sum is σ = 1711215324. Its totient is φ = 200581632.

The previous prime is 639354557. The next prime is 639354589. The reversal of 639354564 is 465453936.

639354564 is a `hidden beast` number, since 6 + 39 + 3 + 54 + 564 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 183873600 + 455480964 = 13560^2 + 21342^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 521737 + ... + 522960.

It is an arithmetic number, because the mean of its divisors is an integer number (47533759).

Almost surely, 2^639354564 is an apocalyptic number.

It is an amenable number.

639354564 is an abundant number, since it is smaller than the sum of its proper divisors (1071860760).

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

639354564 is a wasteful number, since it uses less digits than its factorization.

639354564 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1044724 (or 1044719 counting only the distinct ones).

The product of its digits is 1166400, while the sum is 45.

The square root of 639354564 is about 25285.4615144751. The cubic root of 639354564 is about 861.4840807160.

The spelling of 639354564 in words is "six hundred thirty-nine million, three hundred fifty-four thousand, five hundred sixty-four".