31316643389 has 2 divisors, whose sum is σ = 31316643390. Its totient is φ = 31316643388.

The previous prime is 31316643317. The next prime is 31316643403. The reversal of 31316643389 is 98334661313.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 31305286489 + 11356900 = 176933^2 + 3370^2 .

It is a cyclic number.

It is not a de Polignac number, because 31316643389 - 2¹² = 31316639293 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31316643089) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15658321694 + 15658321695.

It is an arithmetic number, because the mean of its divisors is an integer number (15658321695).

Almost surely, 2^31316643389 is an apocalyptic number.

It is an amenable number.

31316643389 is a deficient number, since it is larger than the sum of its proper divisors (1).

31316643389 is an equidigital number, since it uses as much as digits as its factorization.

31316643389 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 839808, while the sum is 47.

The spelling of 31316643389 in words is "thirty-one billion, three hundred sixteen million, six hundred forty-three thousand, three hundred eighty-nine".