31857403387 has 2 divisors, whose sum is σ = 31857403388. Its totient is φ = 31857403386.

The previous prime is 31857403373. The next prime is 31857403427. The reversal of 31857403387 is 78330475813.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31857403387 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 31857403387.

It is not a weakly prime, because it can be changed into another prime (31857403307) 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, 15928701693 + 15928701694.

It is an arithmetic number, because the mean of its divisors is an integer number (15928701694).

Almost surely, 2^31857403387 is an apocalyptic number.

31857403387 is a deficient number, since it is larger than the sum of its proper divisors (1).

31857403387 is an equidigital number, since it uses as much as digits as its factorization.

31857403387 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1693440, while the sum is 49.

The spelling of 31857403387 in words is "thirty-one billion, eight hundred fifty-seven million, four hundred three thousand, three hundred eighty-seven".