31021321121 has 4 divisors (see below), whose sum is σ = 35452938432. Its totient is φ = 26589703812.

The previous prime is 31021321099. The next prime is 31021321127. The reversal of 31021321121 is 12112312013.

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 not a de Polignac number, because 31021321121 - 2⁶ = 31021321057 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 31021321121.

It is not an unprimeable number, because it can be changed into a prime (31021321127) 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 3 ways as a sum of consecutive naturals, for example, 2215808645 + ... + 2215808658.

It is an arithmetic number, because the mean of its divisors is an integer number (8863234608).

Almost surely, 2^31021321121 is an apocalyptic number.

It is an amenable number.

31021321121 is a deficient number, since it is larger than the sum of its proper divisors (4431617311).

31021321121 is an equidigital number, since it uses as much as digits as its factorization.

31021321121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4431617310.

The product of its (nonzero) digits is 72, while the sum is 17.

Adding to 31021321121 its reverse (12112312013), we get a palindrome (43133633134).

The spelling of 31021321121 in words is "thirty-one billion, twenty-one million, three hundred twenty-one thousand, one hundred twenty-one".