31213220101 has 4 divisors (see below), whose sum is σ = 35672251552. Its totient is φ = 26754188652.

The previous prime is 31213220099. The next prime is 31213220123. The reversal of 31213220101 is 10102231213.

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 not a de Polignac number, because 31213220101 - 2¹ = 31213220099 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31213220161) 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, 2229515715 + ... + 2229515728.

It is an arithmetic number, because the mean of its divisors is an integer number (8918062888).

Almost surely, 2^31213220101 is an apocalyptic number.

It is an amenable number.

31213220101 is a deficient number, since it is larger than the sum of its proper divisors (4459031451).

31213220101 is an equidigital number, since it uses as much as digits as its factorization.

31213220101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4459031450.

The product of its (nonzero) digits is 72, while the sum is 16.

Adding to 31213220101 its reverse (10102231213), we get a palindrome (41315451314).

It can be divided in two parts, 312132 and 20101, that added together give a palindrome (332233).

The spelling of 31213220101 in words is "thirty-one billion, two hundred thirteen million, two hundred twenty thousand, one hundred one".