31857874549 has 2 divisors, whose sum is σ = 31857874550. Its totient is φ = 31857874548.

The previous prime is 31857874493. The next prime is 31857874561. The reversal of 31857874549 is 94547875813.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 30267300625 + 1590573924 = 173975^2 + 39882^2 .

It is a cyclic number.

It is not a de Polignac number, because 31857874549 - 2²⁵ = 31824320117 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31857874949) 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, 15928937274 + 15928937275.

It is an arithmetic number, because the mean of its divisors is an integer number (15928937275).

Almost surely, 2^31857874549 is an apocalyptic number.

It is an amenable number.

31857874549 is a deficient number, since it is larger than the sum of its proper divisors (1).

31857874549 is an equidigital number, since it uses as much as digits as its factorization.

31857874549 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 33868800, while the sum is 61.

The spelling of 31857874549 in words is "thirty-one billion, eight hundred fifty-seven million, eight hundred seventy-four thousand, five hundred forty-nine".