31995993 has 12 divisors (see below), whose sum is σ = 43123920. Its totient is φ = 21100752.

The previous prime is 31995983. The next prime is 31996021. The reversal of 31995993 is 39959913.

It is a happy number.

It is not a de Polignac number, because 31995993 - 2²⁰ = 30947417 is a prime.

It is a Smith number, since the sum of its digits (48) coincides with the sum of the digits of its prime factors.

It is the 5657-th Hogben number.

It is not an unprimeable number, because it can be changed into a prime (31995923) by changing a digit.

It is a nontrivial repunit in base 5656.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 115371 + ... + 115647.

It is an arithmetic number, because the mean of its divisors is an integer number (3593660).

Almost surely, 2^31995993 is an apocalyptic number.

It is an amenable number.

31995993 is a deficient number, since it is larger than the sum of its proper divisors (11127927).

31995993 is an equidigital number, since it uses as much as digits as its factorization.

31995993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 696 (or 419 counting only the distinct ones).

The product of its digits is 295245, while the sum is 48.

The square root of 31995993 is about 5656.5000662954. The cubic root of 31995993 is about 317.4669583488.

The spelling of 31995993 in words is "thirty-one million, nine hundred ninety-five thousand, nine hundred ninety-three".