31860638018 has 24 divisors (see below), whose sum is σ = 52802812524. Its totient is φ = 14407050240.

The previous prime is 31860638011. The next prime is 31860638057. The reversal of 31860638018 is 81083606813.

It can be written as a sum of positive squares in 2 ways, for example, as 26946207409 + 4914430609 = 164153^2 + 70103^2 .

It is a Smith number, since the sum of its digits (44) coincides with the sum of the digits of its prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 31860638018.

It is not an unprimeable number, because it can be changed into a prime (31860638011) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 294371 + ... + 387782.

Almost surely, 2^31860638018 is an apocalyptic number.

31860638018 is a deficient number, since it is larger than the sum of its proper divisors (20942174506).

31860638018 is a wasteful number, since it uses less digits than its factorization.

31860638018 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 682370 (or 682359 counting only the distinct ones).

The product of its (nonzero) digits is 165888, while the sum is 44.

The spelling of 31860638018 in words is "thirty-one billion, eight hundred sixty million, six hundred thirty-eight thousand, eighteen".