31021220999999 has 4 divisors (see below), whose sum is σ = 31021233834936. Its totient is φ = 31021208165064.

The previous prime is 31021220999963. The next prime is 31021221000037. The reversal of 31021220999999 is 99999902212013.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 31021220999999 - 2⁴⁰ = 29921709372223 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 (31021229999999) 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, 1573109 + ... + 8032254.

It is an arithmetic number, because the mean of its divisors is an integer number (7755308458734).

Almost surely, 2^{31021220999999} is an apocalyptic number.

31021220999999 is a deficient number, since it is larger than the sum of its proper divisors (12834937).

31021220999999 is an equidigital number, since it uses as much as digits as its factorization.

31021220999999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12834936.

The product of its (nonzero) digits is 12754584, while the sum is 65.

The spelling of 31021220999999 in words is "thirty-one trillion, twenty-one billion, two hundred twenty million, nine hundred ninety-nine thousand, nine hundred ninety-nine".