131581635638 has 16 divisors (see below), whose sum is σ = 209008251504. Its totient is φ = 61913168640.

The previous prime is 131581635569. The next prime is 131581635641. The reversal of 131581635638 is 836536185131.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 48506 + ... + 515282.

It is an arithmetic number, because the mean of its divisors is an integer number (13063015719).

Almost surely, 2^131581635638 is an apocalyptic number.

131581635638 is a deficient number, since it is larger than the sum of its proper divisors (77426615866).

131581635638 is a wasteful number, since it uses less digits than its factorization.

131581635638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 475087.

The product of its digits is 1555200, while the sum is 50.

The spelling of 131581635638 in words is "one hundred thirty-one billion, five hundred eighty-one million, six hundred thirty-five thousand, six hundred thirty-eight".