31637996018 has 4 divisors (see below), whose sum is σ = 47456994030. Its totient is φ = 15818998008.

The previous prime is 31637996017. The next prime is 31637996021. The reversal of 31637996018 is 81069973613.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 81069973613 = 70381 ⋅1151873.

It can be written as a sum of positive squares in only one way, i.e., 23512235569 + 8125760449 = 153337^2 + 90143^2 .

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (31637996017) by changing a digit.

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 as a sum of consecutive naturals, namely, 7909499003 + ... + 7909499006.

Almost surely, 2^31637996018 is an apocalyptic number.

31637996018 is a deficient number, since it is larger than the sum of its proper divisors (15818998012).

31637996018 is a wasteful number, since it uses less digits than its factorization.

31637996018 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15818998011.

The product of its (nonzero) digits is 1469664, while the sum is 53.

The spelling of 31637996018 in words is "thirty-one billion, six hundred thirty-seven million, nine hundred ninety-six thousand, eighteen".