117213979138 has 4 divisors (see below), whose sum is σ = 175820968710. Its totient is φ = 58606989568.

The previous prime is 117213979117. The next prime is 117213979139. The reversal of 117213979138 is 831979312711.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 831979312711 = 36929 ⋅22529159.

It can be written as a sum of positive squares in only one way, i.e., 77191175889 + 40022803249 = 277833^2 + 200057^2 .

It is not an unprimeable number, because it can be changed into a prime (117213979139) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 29303494783 + ... + 29303494786.

Almost surely, 2^117213979138 is an apocalyptic number.

117213979138 is a deficient number, since it is larger than the sum of its proper divisors (58606989572).

117213979138 is an equidigital number, since it uses as much as digits as its factorization.

117213979138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 58606989571.

The product of its digits is 571536, while the sum is 52.

The spelling of 117213979138 in words is "one hundred seventeen billion, two hundred thirteen million, nine hundred seventy-nine thousand, one hundred thirty-eight".