31375316321 has 2 divisors, whose sum is σ = 31375316322. Its totient is φ = 31375316320.

The previous prime is 31375316299. The next prime is 31375316327. The reversal of 31375316321 is 12361357313.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20368998400 + 11006317921 = 142720^2 + 104911^2 .

It is an emirp because it is prime and its reverse (12361357313) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 31375316321 - 2⁶ = 31375316257 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 (31375316327) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15687658160 + 15687658161.

It is an arithmetic number, because the mean of its divisors is an integer number (15687658161).

Almost surely, 2^31375316321 is an apocalyptic number.

It is an amenable number.

31375316321 is a deficient number, since it is larger than the sum of its proper divisors (1).

31375316321 is an equidigital number, since it uses as much as digits as its factorization.

31375316321 is an evil number, because the sum of its binary digits is even.

The product of its digits is 34020, while the sum is 35.

The spelling of 31375316321 in words is "thirty-one billion, three hundred seventy-five million, three hundred sixteen thousand, three hundred twenty-one".