31000311997 has 2 divisors, whose sum is σ = 31000311998. Its totient is φ = 31000311996.

The previous prime is 31000311983. The next prime is 31000312043. The reversal of 31000311997 is 79911300013.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 30455136196 + 545175801 = 174514^2 + 23349^2 .

It is a cyclic number.

It is not a de Polignac number, because 31000311997 - 2²⁷ = 30866094269 is a prime.

It is a super-2 number, since 2×31000311997² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31000311497) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15500155998 + 15500155999.

It is an arithmetic number, because the mean of its divisors is an integer number (15500155999).

Almost surely, 2^31000311997 is an apocalyptic number.

It is an amenable number.

31000311997 is a deficient number, since it is larger than the sum of its proper divisors (1).

31000311997 is an equidigital number, since it uses as much as digits as its factorization.

31000311997 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5103, while the sum is 34.

The spelling of 31000311997 in words is "thirty-one billion, three hundred eleven thousand, nine hundred ninety-seven".