31966918121 has 4 divisors (see below), whose sum is σ = 32067760452. Its totient is φ = 31866075792.

The previous prime is 31966918111. The next prime is 31966918189. The reversal of 31966918121 is 12181966913.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 522762496 + 31444155625 = 22864^2 + 177325^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31966918121 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31966918111) 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, 50420690 + ... + 50421323.

It is an arithmetic number, because the mean of its divisors is an integer number (8016940113).

Almost surely, 2^31966918121 is an apocalyptic number.

It is an amenable number.

31966918121 is a deficient number, since it is larger than the sum of its proper divisors (100842331).

31966918121 is a wasteful number, since it uses less digits than its factorization.

31966918121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 100842330.

The product of its digits is 139968, while the sum is 47.

The spelling of 31966918121 in words is "thirty-one billion, nine hundred sixty-six million, nine hundred eighteen thousand, one hundred twenty-one".