638840740025 has 12 divisors (see below), whose sum is σ = 796143240000. Its totient is φ = 508504384080.

The previous prime is 638840740019. The next prime is 638840740049. The reversal of 638840740025 is 520047048836.

It is not a de Polignac number, because 638840740025 - 2⁴ = 638840740009 is a prime.

It is a super-2 number, since 2×638840740025² (a number of 24 digits) contains 22 as substring.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 64200125 + ... + 64210074.

It is an arithmetic number, because the mean of its divisors is an integer number (66345270000).

Almost surely, 2^638840740025 is an apocalyptic number.

It is an amenable number.

638840740025 is a deficient number, since it is larger than the sum of its proper divisors (157302499975).

638840740025 is a wasteful number, since it uses less digits than its factorization.

638840740025 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 128410408 (or 128410403 counting only the distinct ones).

The product of its (nonzero) digits is 1290240, while the sum is 47.

The spelling of 638840740025 in words is "six hundred thirty-eight billion, eight hundred forty million, seven hundred forty thousand, twenty-five".