31321220021021 has 32 divisors (see below), whose sum is σ = 37663042314240. Its totient is φ = 25466459521536.

The previous prime is 31321220021009. The next prime is 31321220021033. The reversal of 31321220021021 is 12012002212313.

It is an interprime number because it is at equal distance from previous prime (31321220021009) and next prime (31321220021033).

It is not a de Polignac number, because 31321220021021 - 2¹⁴ = 31321220004637 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 31321220020984 and 31321220021002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31321220021041) 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, 9095885 + ... + 12057261.

It is an arithmetic number, because the mean of its divisors is an integer number (1176970072320).

Almost surely, 2^{31321220021021} is an apocalyptic number.

It is an amenable number.

31321220021021 is a deficient number, since it is larger than the sum of its proper divisors (6341822293219).

31321220021021 is a wasteful number, since it uses less digits than its factorization.

31321220021021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2961953.

The product of its (nonzero) digits is 288, while the sum is 20.

Adding to 31321220021021 its reverse (12012002212313), we get a palindrome (43333222233334).

The spelling of 31321220021021 in words is "thirty-one trillion, three hundred twenty-one billion, two hundred twenty million, twenty-one thousand, twenty-one".