31621117 has 4 divisors (see below), whose sum is σ = 34495776. Its totient is φ = 28746460.

The previous prime is 31621097. The next prime is 31621123. The reversal of 31621117 is 71112613.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31621117 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31621157) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1437313 + ... + 1437334.

It is an arithmetic number, because the mean of its divisors is an integer number (8623944).

Almost surely, 2^31621117 is an apocalyptic number.

It is an amenable number.

31621117 is a deficient number, since it is larger than the sum of its proper divisors (2874659).

31621117 is a wasteful number, since it uses less digits than its factorization.

31621117 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2874658.

The product of its digits is 252, while the sum is 22.

The square root of 31621117 is about 5623.2656881922. The cubic root of 31621117 is about 316.2222339144. Note that the first 4 decimals are identical.

The spelling of 31621117 in words is "thirty-one million, six hundred twenty-one thousand, one hundred seventeen".