31898991057 has 4 divisors (see below), whose sum is σ = 42531988080. Its totient is φ = 21265994036.

The previous prime is 31898991037. The next prime is 31898991071. The reversal of 31898991057 is 75019989813.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 31898991057 - 2⁶ = 31898990993 is a prime.

It is not an unprimeable number, because it can be changed into a prime (31898991037) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5316498507 + ... + 5316498512.

It is an arithmetic number, because the mean of its divisors is an integer number (10632997020).

Almost surely, 2^31898991057 is an apocalyptic number.

It is an amenable number.

31898991057 is a deficient number, since it is larger than the sum of its proper divisors (10632997023).

31898991057 is a wasteful number, since it uses less digits than its factorization.

31898991057 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10632997022.

The product of its (nonzero) digits is 4898880, while the sum is 60.

The spelling of 31898991057 in words is "thirty-one billion, eight hundred ninety-eight million, nine hundred ninety-one thousand, fifty-seven".