313121111021 has 4 divisors (see below), whose sum is σ = 313260712512. Its totient is φ = 312981509532.

The previous prime is 313121110997. The next prime is 313121111057. The reversal of 313121111021 is 120111121313.

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-313121111021 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 (313121110021) 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, 69797381 + ... + 69801866.

It is an arithmetic number, because the mean of its divisors is an integer number (78315178128).

Almost surely, 2^313121111021 is an apocalyptic number.

It is an amenable number.

313121111021 is a deficient number, since it is larger than the sum of its proper divisors (139601491).

313121111021 is a wasteful number, since it uses less digits than its factorization.

313121111021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 139601490.

The product of its (nonzero) digits is 36, while the sum is 17.

Adding to 313121111021 its reverse (120111121313), we get a palindrome (433232232334).

The spelling of 313121111021 in words is "three hundred thirteen billion, one hundred twenty-one million, one hundred eleven thousand, twenty-one".