639037634 has 8 divisors (see below), whose sum is σ = 959021580. Its totient is φ = 319363776.

The previous prime is 639037631. The next prime is 639037639. The reversal of 639037634 is 436730936.

It can be written as a sum of positive squares in 2 ways, for example, as 638320225 + 717409 = 25265^2 + 847^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a junction number, because it is equal to n+sod(n) for n = 639037591 and 639037600.

It is not an unprimeable number, because it can be changed into a prime (639037631) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 72299 + ... + 80654.

Almost surely, 2^639037634 is an apocalyptic number.

639037634 is a deficient number, since it is larger than the sum of its proper divisors (319983946).

639037634 is a wasteful number, since it uses less digits than its factorization.

639037634 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 155044.

The product of its (nonzero) digits is 244944, while the sum is 41.

The square root of 639037634 is about 25279.1936975846. The cubic root of 639037634 is about 861.3417104302.

The spelling of 639037634 in words is "six hundred thirty-nine million, thirty-seven thousand, six hundred thirty-four".