31591094042 has 4 divisors (see below), whose sum is σ = 47386641066. Its totient is φ = 15795547020.

The previous prime is 31591094023. The next prime is 31591094047. The reversal of 31591094042 is 24049019513.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 19732101841 + 11858992201 = 140471^2 + 108899^2 .

It is a junction number, because it is equal to n+sod(n) for n = 31591093987 and 31591094005.

It is not an unprimeable number, because it can be changed into a prime (31591094047) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7897773509 + ... + 7897773512.

Almost surely, 2^31591094042 is an apocalyptic number.

31591094042 is a deficient number, since it is larger than the sum of its proper divisors (15795547024).

31591094042 is a wasteful number, since it uses less digits than its factorization.

31591094042 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15795547023.

The product of its (nonzero) digits is 38880, while the sum is 38.

The spelling of 31591094042 in words is "thirty-one billion, five hundred ninety-one million, ninety-four thousand, forty-two".