117681979 has 4 divisors (see below), whose sum is σ = 117970120. Its totient is φ = 117393840.

The previous prime is 117681923. The next prime is 117681989. The reversal of 117681979 is 979186711.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 979186711 = 29 ⋅33765059.

It is a cyclic number.

It is not a de Polignac number, because 117681979 - 2²¹ = 115584827 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (117681919) 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, 143457 + ... + 144274.

It is an arithmetic number, because the mean of its divisors is an integer number (29492530).

Almost surely, 2^117681979 is an apocalyptic number.

117681979 is a deficient number, since it is larger than the sum of its proper divisors (288141).

117681979 is an equidigital number, since it uses as much as digits as its factorization.

117681979 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 288140.

The product of its digits is 190512, while the sum is 49.

The square root of 117681979 is about 10848.1325120963. The cubic root of 117681979 is about 490.0457808121.

The spelling of 117681979 in words is "one hundred seventeen million, six hundred eighty-one thousand, nine hundred seventy-nine".