31133311020021 has 32 divisors (see below), whose sum is σ = 47680778373120. Its totient is φ = 17700858736704.

The previous prime is 31133311020013. The next prime is 31133311020061. The reversal of 31133311020021 is 12002011333113.

It is a happy number.

It is not a de Polignac number, because 31133311020021 - 2³ = 31133311020013 is a prime.

It is a super-2 number, since 2×31133311020021² (a number of 28 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 31133311020021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31133311020011) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1321210 + ... + 8000763.

It is an arithmetic number, because the mean of its divisors is an integer number (1490024324160).

Almost surely, 2^{31133311020021} is an apocalyptic number.

It is an amenable number.

31133311020021 is a deficient number, since it is larger than the sum of its proper divisors (16547467353099).

31133311020021 is a wasteful number, since it uses less digits than its factorization.

31133311020021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9322785.

The product of its (nonzero) digits is 324, while the sum is 21.

Adding to 31133311020021 its reverse (12002011333113), we get a palindrome (43135322353134).

The spelling of 31133311020021 in words is "thirty-one trillion, one hundred thirty-three billion, three hundred eleven million, twenty thousand, twenty-one".