31213212211220 has 36 divisors (see below), whose sum is σ = 70977736414620. Its totient is φ = 11524878353664.

The previous prime is 31213212211219. The next prime is 31213212211241. The reversal of 31213212211220 is 2211221231213.

It can be written as a sum of positive squares in 6 ways, for example, as 11792603249296 + 19420608961924 = 3434036^2 + 4406882^2 .

It is a congruent number.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 4617335705 + ... + 4617342464.

It is an arithmetic number, because the mean of its divisors is an integer number (1971603789295).

Almost surely, 2^{31213212211220} is an apocalyptic number.

It is an amenable number.

31213212211220 is an abundant number, since it is smaller than the sum of its proper divisors (39764524203400).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

31213212211220 is a wasteful number, since it uses less digits than its factorization.

31213212211220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9234678204 (or 9234678189 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 23.

Adding to 31213212211220 its reverse (2211221231213), we get a palindrome (33424433442433).

The spelling of 31213212211220 in words is "thirty-one trillion, two hundred thirteen billion, two hundred twelve million, two hundred eleven thousand, two hundred twenty".