636111678138 has 32 divisors (see below), whose sum is σ = 1273785803136. Its totient is φ = 211776964608.

The previous prime is 636111678131. The next prime is 636111678151. The reversal of 636111678138 is 831876111636.

It is not an unprimeable number, because it can be changed into a prime (636111678131) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 19428870 + ... + 19461582.

It is an arithmetic number, because the mean of its divisors is an integer number (39805806348).

Almost surely, 2^636111678138 is an apocalyptic number.

636111678138 is an abundant number, since it is smaller than the sum of its proper divisors (637674124998).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

636111678138 is a wasteful number, since it uses less digits than its factorization.

636111678138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36598.

The product of its digits is 870912, while the sum is 51.

The spelling of 636111678138 in words is "six hundred thirty-six billion, one hundred eleven million, six hundred seventy-eight thousand, one hundred thirty-eight".