31881160457 has 4 divisors (see below), whose sum is σ = 31881541956. Its totient is φ = 31880778960.

The previous prime is 31881160427. The next prime is 31881160481. The reversal of 31881160457 is 75406118813.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 75406118813 = 37643 ⋅2003191.

It can be written as a sum of positive squares in 2 ways, for example, as 2304384016 + 29576776441 = 48004^2 + 171979^2 .

It is a cyclic number.

It is not a de Polignac number, because 31881160457 - 2¹⁰ = 31881159433 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31881160427) 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, 5294 + ... + 252567.

It is an arithmetic number, because the mean of its divisors is an integer number (7970385489).

Almost surely, 2^31881160457 is an apocalyptic number.

It is an amenable number.

31881160457 is a deficient number, since it is larger than the sum of its proper divisors (381499).

31881160457 is a wasteful number, since it uses less digits than its factorization.

31881160457 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 381498.

The product of its (nonzero) digits is 161280, while the sum is 44.

The spelling of 31881160457 in words is "thirty-one billion, eight hundred eighty-one million, one hundred sixty thousand, four hundred fifty-seven".