79640510138 has 32 divisors (see below), whose sum is σ = 137966526720. Its totient is φ = 33772515840.

The previous prime is 79640510107. The next prime is 79640510167. The reversal of 79640510138 is 83101504697.

It is a super-2 number, since 2×79640510138² (a number of 23 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1098698 + ... + 1168938.

It is an arithmetic number, because the mean of its divisors is an integer number (4311453960).

Almost surely, 2^79640510138 is an apocalyptic number.

79640510138 is a deficient number, since it is larger than the sum of its proper divisors (58326016582).

79640510138 is a wasteful number, since it uses less digits than its factorization.

79640510138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71102.

The product of its (nonzero) digits is 181440, while the sum is 44.

The spelling of 79640510138 in words is "seventy-nine billion, six hundred forty million, five hundred ten thousand, one hundred thirty-eight".