31157577938 has 4 divisors (see below), whose sum is σ = 46736366910. Its totient is φ = 15578788968.

The previous prime is 31157577833. The next prime is 31157577961. The reversal of 31157577938 is 83977575113.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 83977575113 = 4783 ⋅17557511.

It can be written as a sum of positive squares in only one way, i.e., 25495466929 + 5662111009 = 159673^2 + 75247^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7789394483 + ... + 7789394486.

Almost surely, 2^31157577938 is an apocalyptic number.

31157577938 is a deficient number, since it is larger than the sum of its proper divisors (15578788972).

31157577938 is a wasteful number, since it uses less digits than its factorization.

31157577938 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15578788971.

The product of its digits is 5556600, while the sum is 56.

The spelling of 31157577938 in words is "thirty-one billion, one hundred fifty-seven million, five hundred seventy-seven thousand, nine hundred thirty-eight".