31239944136 has 64 divisors (see below), whose sum is σ = 87440126400. Its totient is φ = 10333814400.

The previous prime is 31239944101. The next prime is 31239944159. The reversal of 31239944136 is 63144993213.

It is a happy number.

It is a nude number because it is divisible by every one of its digits.

It is a junction number, because it is equal to n+sod(n) for n = 31239944091 and 31239944100.

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, 523725 + ... + 580316.

It is an arithmetic number, because the mean of its divisors is an integer number (1366251975).

Almost surely, 2^31239944136 is an apocalyptic number.

31239944136 is a gapful number since it is divisible by the number (36) formed by its first and last digit.

It is an amenable number.

31239944136 is an abundant number, since it is smaller than the sum of its proper divisors (56200182264).

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

31239944136 is a wasteful number, since it uses less digits than its factorization.

31239944136 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1104187 (or 1104177 counting only the distinct ones).

The product of its digits is 419904, while the sum is 45.

The spelling of 31239944136 in words is "thirty-one billion, two hundred thirty-nine million, nine hundred forty-four thousand, one hundred thirty-six".