31399488761 has 2 divisors, whose sum is σ = 31399488762. Its totient is φ = 31399488760.

The previous prime is 31399488751. The next prime is 31399488803. The reversal of 31399488761 is 16788499313.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 25798463161 + 5601025600 = 160619^2 + 74840^2 .

It is a cyclic number.

It is not a de Polignac number, because 31399488761 - 2³⁰ = 30325746937 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 31399488761.

It is not a weakly prime, because it can be changed into another prime (31399488751) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15699744380 + 15699744381.

It is an arithmetic number, because the mean of its divisors is an integer number (15699744381).

Almost surely, 2^31399488761 is an apocalyptic number.

It is an amenable number.

31399488761 is a deficient number, since it is larger than the sum of its proper divisors (1).

31399488761 is an equidigital number, since it uses as much as digits as its factorization.

31399488761 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 7838208, while the sum is 59.

The spelling of 31399488761 in words is "thirty-one billion, three hundred ninety-nine million, four hundred eighty-eight thousand, seven hundred sixty-one".