31622561 has 4 divisors (see below), whose sum is σ = 31679892. Its totient is φ = 31565232.

The previous prime is 31622537. The next prime is 31622579. The reversal of 31622561 is 16522613.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 16522613 = 79 ⋅209147.

It can be written as a sum of positive squares in 2 ways, for example, as 5202961 + 26419600 = 2281^2 + 5140^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31622561 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 31622561.

It is not an unprimeable number, because it can be changed into a prime (31621561) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 27830 + ... + 28943.

It is an arithmetic number, because the mean of its divisors is an integer number (7919973).

Almost surely, 2^31622561 is an apocalyptic number.

It is an amenable number.

31622561 is a deficient number, since it is larger than the sum of its proper divisors (57331).

31622561 is an equidigital number, since it uses as much as digits as its factorization.

31622561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 57330.

The product of its digits is 2160, while the sum is 26.

The square root of 31622561 is about 5623.3940818691. The cubic root of 31622561 is about 316.2270473429.

The spelling of 31622561 in words is "thirty-one million, six hundred twenty-two thousand, five hundred sixty-one".