639542936 has 16 divisors (see below), whose sum is σ = 1209756600. Its totient is φ = 316941184.

The previous prime is 639542929. The next prime is 639542951. The reversal of 639542936 is 639245936.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 352826 + ... + 354633.

Almost surely, 2^639542936 is an apocalyptic number.

It is an amenable number.

639542936 is a deficient number, since it is larger than the sum of its proper divisors (570213664).

639542936 is a wasteful number, since it uses less digits than its factorization.

639542936 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 707578 (or 707574 counting only the distinct ones).

The product of its digits is 1049760, while the sum is 47.

The square root of 639542936 is about 25289.1861474425. The cubic root of 639542936 is about 861.5686782949.

The spelling of 639542936 in words is "six hundred thirty-nine million, five hundred forty-two thousand, nine hundred thirty-six".