639318972525 has 24 divisors (see below), whose sum is σ = 1112639337120. Its totient is φ = 323024322240.

The previous prime is 639318972521. The next prime is 639318972527. The reversal of 639318972525 is 525279813936.

It is not a de Polignac number, because 639318972525 - 2² = 639318972521 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (639318972521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 224321022 + ... + 224323871.

It is an arithmetic number, because the mean of its divisors is an integer number (46359972380).

Almost surely, 2^639318972525 is an apocalyptic number.

It is an amenable number.

639318972525 is a deficient number, since it is larger than the sum of its proper divisors (473320364595).

639318972525 is a wasteful number, since it uses less digits than its factorization.

639318972525 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 448644925 (or 448644920 counting only the distinct ones).

The product of its digits is 24494400, while the sum is 60.

The spelling of 639318972525 in words is "six hundred thirty-nine billion, three hundred eighteen million, nine hundred seventy-two thousand, five hundred twenty-five".