31995961 has 4 divisors (see below), whose sum is σ = 33099300. Its totient is φ = 30892624.

The previous prime is 31995959. The next prime is 31995983. The reversal of 31995961 is 16959913.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 16959913 = 19 ⋅892627.

It can be written as a sum of positive squares in 2 ways, for example, as 16353936 + 15642025 = 4044^2 + 3955^2 .

It is a cyclic number.

It is not a de Polignac number, because 31995961 - 2¹ = 31995959 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31995911) 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, 551626 + ... + 551683.

It is an arithmetic number, because the mean of its divisors is an integer number (8274825).

Almost surely, 2^31995961 is an apocalyptic number.

It is an amenable number.

31995961 is a deficient number, since it is larger than the sum of its proper divisors (1103339).

31995961 is a wasteful number, since it uses less digits than its factorization.

31995961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1103338.

The product of its digits is 65610, while the sum is 43.

The square root of 31995961 is about 5656.4972376905. The cubic root of 31995961 is about 317.4668525132.

The spelling of 31995961 in words is "thirty-one million, nine hundred ninety-five thousand, nine hundred sixty-one".