31032431440 has 20 divisors (see below), whose sum is σ = 72150403284. Its totient is φ = 12412972544.

The previous prime is 31032431399. The next prime is 31032431449. The reversal of 31032431440 is 4413423013.

It can be written as a sum of positive squares in 2 ways, for example, as 12924961344 + 18107470096 = 113688^2 + 134564^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31032431449) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 193952617 + ... + 193952776.

Almost surely, 2^31032431440 is an apocalyptic number.

It is an amenable number.

31032431440 is an abundant number, since it is smaller than the sum of its proper divisors (41117971844).

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

31032431440 is a wasteful number, since it uses less digits than its factorization.

31032431440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 387905406 (or 387905400 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 25.

Adding to 31032431440 its reverse (4413423013), we get a palindrome (35445854453).

The spelling of 31032431440 in words is "thirty-one billion, thirty-two million, four hundred thirty-one thousand, four hundred forty".