31131497819 has 2 divisors, whose sum is σ = 31131497820. Its totient is φ = 31131497818.

The previous prime is 31131497797. The next prime is 31131497827. The reversal of 31131497819 is 91879413113.

It is a happy number.

It is a strong prime.

It is an emirp because it is prime and its reverse (91879413113) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 31131497819 - 2⁸ = 31131497563 is a prime.

It is a super-2 number, since 2×31131497819² (a number of 22 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (31131497849) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15565748909 + 15565748910.

It is an arithmetic number, because the mean of its divisors is an integer number (15565748910).

Almost surely, 2^31131497819 is an apocalyptic number.

31131497819 is a deficient number, since it is larger than the sum of its proper divisors (1).

31131497819 is an equidigital number, since it uses as much as digits as its factorization.

31131497819 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 163296, while the sum is 47.

The spelling of 31131497819 in words is "thirty-one billion, one hundred thirty-one million, four hundred ninety-seven thousand, eight hundred nineteen".