31312203110021 has 4 divisors (see below), whose sum is σ = 31318832842272. Its totient is φ = 31305573377772.

The previous prime is 31312203109997. The next prime is 31312203110039. The reversal of 31312203110021 is 12001130221313.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31312203110021 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 31312203109975 and 31312203110002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31312203910021) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3314859041 + ... + 3314868486.

It is an arithmetic number, because the mean of its divisors is an integer number (7829708210568).

Almost surely, 2^{31312203110021} is an apocalyptic number.

It is an amenable number.

31312203110021 is a deficient number, since it is larger than the sum of its proper divisors (6629732251).

31312203110021 is an equidigital number, since it uses as much as digits as its factorization.

31312203110021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6629732250.

The product of its (nonzero) digits is 216, while the sum is 20.

Adding to 31312203110021 its reverse (12001130221313), we get a palindrome (43313333331334).

The spelling of 31312203110021 in words is "thirty-one trillion, three hundred twelve billion, two hundred three million, one hundred ten thousand, twenty-one".