312221213121 has 16 divisors (see below), whose sum is σ = 445327049664. Its totient is φ = 193883879424.

The previous prime is 312221213111. The next prime is 312221213153. The reversal of 312221213121 is 121312122213.

It is not a de Polignac number, because 312221213121 - 2⁵ = 312221213089 is a prime.

It is not an unprimeable number, because it can be changed into a prime (312221213111) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 31551675 + ... + 31561568.

It is an arithmetic number, because the mean of its divisors is an integer number (27832940604).

Almost surely, 2^312221213121 is an apocalyptic number.

It is an amenable number.

312221213121 is a deficient number, since it is larger than the sum of its proper divisors (133105836543).

312221213121 is a wasteful number, since it uses less digits than its factorization.

312221213121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 63113360.

The product of its digits is 288, while the sum is 21.

Adding to 312221213121 its reverse (121312122213), we get a palindrome (433533335334).

The spelling of 312221213121 in words is "three hundred twelve billion, two hundred twenty-one million, two hundred thirteen thousand, one hundred twenty-one".