31513405299991 has 2 divisors, whose sum is σ = 31513405299992. Its totient is φ = 31513405299990.

The previous prime is 31513405299989. The next prime is 31513405300019. The reversal of 31513405299991 is 19999250431513.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 31513405299991 - 2¹ = 31513405299989 is a prime.

Together with 31513405299989, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31513405299791) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15756702649995 + 15756702649996.

It is an arithmetic number, because the mean of its divisors is an integer number (15756702649996).

Almost surely, 2^{31513405299991} is an apocalyptic number.

31513405299991 is a deficient number, since it is larger than the sum of its proper divisors (1).

31513405299991 is an equidigital number, since it uses as much as digits as its factorization.

31513405299991 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 11809800, while the sum is 61.

The spelling of 31513405299991 in words is "thirty-one trillion, five hundred thirteen billion, four hundred five million, two hundred ninety-nine thousand, nine hundred ninety-one".