31221212211 has 64 divisors (see below), whose sum is σ = 53857981440. Its totient is φ = 17505745920.

The previous prime is 31221212203. The next prime is 31221212261. The reversal of 31221212211 is 11221212213.

It is not a de Polignac number, because 31221212211 - 2³ = 31221212203 is a prime.

It is not an unprimeable number, because it can be changed into a prime (31221212201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 5104291 + ... + 5110403.

It is an arithmetic number, because the mean of its divisors is an integer number (841530960).

Almost surely, 2^31221212211 is an apocalyptic number.

31221212211 is a deficient number, since it is larger than the sum of its proper divisors (22636769229).

31221212211 is a wasteful number, since it uses less digits than its factorization.

31221212211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6633 (or 6627 counting only the distinct ones).

The product of its digits is 96, while the sum is 18.

Adding to 31221212211 its reverse (11221212213), we get a palindrome (42442424424).

It can be divided in two parts, 312212 and 12211, that added together give a palindrome (324423).

The spelling of 31221212211 in words is "thirty-one billion, two hundred twenty-one million, two hundred twelve thousand, two hundred eleven".