31986040840 has 64 divisors (see below), whose sum is σ = 77570685360. Its totient is φ = 11800166400.

The previous prime is 31986040837. The next prime is 31986040859. The reversal of 31986040840 is 4804068913.

It can be written as a sum of positive squares in 8 ways, for example, as 123076836 + 31862964004 = 11094^2 + 178502^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 598912 + ... + 650128.

Almost surely, 2^31986040840 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31986040840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38785342680).

31986040840 is an abundant number, since it is smaller than the sum of its proper divisors (45584644520).

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

31986040840 is a wasteful number, since it uses less digits than its factorization.

31986040840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 52442 (or 52438 counting only the distinct ones).

The product of its (nonzero) digits is 165888, while the sum is 43.

The spelling of 31986040840 in words is "thirty-one billion, nine hundred eighty-six million, forty thousand, eight hundred forty".