31987078913 has 2 divisors, whose sum is σ = 31987078914. Its totient is φ = 31987078912.

The previous prime is 31987078897. The next prime is 31987078931.

31987078913 is nontrivially palindromic in base 10.

Together with next prime (31987078931) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 27712926784 + 4274152129 = 166472^2 + 65377^2 .

It is a palprime.

It is a cyclic number.

It is not a de Polignac number, because 31987078913 - 2⁴ = 31987078897 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (31987078973) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15993539456 + 15993539457.

It is an arithmetic number, because the mean of its divisors is an integer number (15993539457).

Almost surely, 2^31987078913 is an apocalyptic number.

It is an amenable number.

31987078913 is a deficient number, since it is larger than the sum of its proper divisors (1).

31987078913 is an equidigital number, since it uses as much as digits as its factorization.

31987078913 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2286144, while the sum is 56.

The spelling of 31987078913 in words is "thirty-one billion, nine hundred eighty-seven million, seventy-eight thousand, nine hundred thirteen".