31356864078389 has 2 divisors, whose sum is σ = 31356864078390. Its totient is φ = 31356864078388.

The previous prime is 31356864078383. The next prime is 31356864078413. The reversal of 31356864078389 is 98387046865313.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 28981350865489 + 2375513212900 = 5383433^2 + 1541270^2 .

It is a cyclic number.

It is not a de Polignac number, because 31356864078389 - 2³⁶ = 31288144601653 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31356864078383) 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, 15678432039194 + 15678432039195.

It is an arithmetic number, because the mean of its divisors is an integer number (15678432039195).

Almost surely, 2^{31356864078389} is an apocalyptic number.

It is an amenable number.

31356864078389 is a deficient number, since it is larger than the sum of its proper divisors (1).

31356864078389 is an equidigital number, since it uses as much as digits as its factorization.

31356864078389 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 627056640, while the sum is 71.

The spelling of 31356864078389 in words is "thirty-one trillion, three hundred fifty-six billion, eight hundred sixty-four million, seventy-eight thousand, three hundred eighty-nine".