117911978 has 4 divisors (see below), whose sum is σ = 176867970. Its totient is φ = 58955988.

The previous prime is 117911957. The next prime is 117912001. The reversal of 117911978 is 879119711.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 879119711 = 191 ⋅4602721.

It can be written as a sum of positive squares in only one way, i.e., 112635769 + 5276209 = 10613^2 + 2297^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 29477993 + ... + 29477996.

Almost surely, 2^117911978 is an apocalyptic number.

117911978 is a deficient number, since it is larger than the sum of its proper divisors (58955992).

117911978 is an equidigital number, since it uses as much as digits as its factorization.

117911978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 58955991.

The product of its digits is 31752, while the sum is 44.

The square root of 117911978 is about 10858.7281944066. The cubic root of 117911978 is about 490.3648234071.

The spelling of 117911978 in words is "one hundred seventeen million, nine hundred eleven thousand, nine hundred seventy-eight".