3131221100021 has 12 divisors (see below), whose sum is σ = 3800807867232. Its totient is φ = 2567212329528.

The previous prime is 3131221100011. The next prime is 3131221100069. The reversal of 3131221100021 is 1200011221313.

3131221100021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 3131221100021 - 2²² = 3131216905717 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 (3131221100011) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1389183035 + ... + 1389185288.

It is an arithmetic number, because the mean of its divisors is an integer number (316733988936).

Almost surely, 2^{3131221100021} is an apocalyptic number.

It is an amenable number.

3131221100021 is a deficient number, since it is larger than the sum of its proper divisors (669586767211).

3131221100021 is a wasteful number, since it uses less digits than its factorization.

3131221100021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2778368360 (or 2778368353 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 17.

Adding to 3131221100021 its reverse (1200011221313), we get a palindrome (4331232321334).

The spelling of 3131221100021 in words is "three trillion, one hundred thirty-one billion, two hundred twenty-one million, one hundred thousand, twenty-one".