3131331021 has 64 divisors (see below), whose sum is σ = 5957898240. Its totient is φ = 1579849920.

The previous prime is 3131331019. The next prime is 3131331059. The reversal of 3131331021 is 1201331313.

It is a happy number.

3131331021 is a `hidden beast` number, since 313 + 1 + 331 + 0 + 21 = 666.

3131331021 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 3131331021 - 2¹ = 3131331019 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 3131330985 and 3131331003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3131331221) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 28806 + ... + 84216.

It is an arithmetic number, because the mean of its divisors is an integer number (93092160).

Almost surely, 2^3131331021 is an apocalyptic number.

It is an amenable number.

3131331021 is a deficient number, since it is larger than the sum of its proper divisors (2826567219).

3131331021 is a wasteful number, since it uses less digits than its factorization.

3131331021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55463 (or 55457 counting only the distinct ones).

The product of its (nonzero) digits is 162, while the sum is 18.

The square root of 3131331021 is about 55958.2971595813. The cubic root of 3131331021 is about 1462.9955107292.

Adding to 3131331021 its reverse (1201331313), we get a palindrome (4332662334).

The spelling of 3131331021 in words is "three billion, one hundred thirty-one million, three hundred thirty-one thousand, twenty-one".