31220213312131 has 2 divisors, whose sum is σ = 31220213312132. Its totient is φ = 31220213312130.

The previous prime is 31220213312077. The next prime is 31220213312207. The reversal of 31220213312131 is 13121331202213.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 31220213312131 - 2²⁷ = 31220079094403 is a prime.

It is a super-2 number, since 2×31220213312131² (a number of 28 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 31220213312096 and 31220213312105.

It is not a weakly prime, because it can be changed into another prime (31220213318131) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15610106656065 + 15610106656066.

It is an arithmetic number, because the mean of its divisors is an integer number (15610106656066).

Almost surely, 2^{31220213312131} is an apocalyptic number.

31220213312131 is a deficient number, since it is larger than the sum of its proper divisors (1).

31220213312131 is an equidigital number, since it uses as much as digits as its factorization.

31220213312131 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1296, while the sum is 25.

Adding to 31220213312131 its reverse (13121331202213), we get a palindrome (44341544514344).

The spelling of 31220213312131 in words is "thirty-one trillion, two hundred twenty billion, two hundred thirteen million, three hundred twelve thousand, one hundred thirty-one".