118517681 has 4 divisors (see below), whose sum is σ = 122340864. Its totient is φ = 114694500.

The previous prime is 118517669. The next prime is 118517701. The reversal of 118517681 is 186715811.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 186715811 = 17 ⋅10983283.

It is a cyclic number.

It is not a de Polignac number, because 118517681 - 2²⁶ = 51408817 is a prime.

It is a super-2 number, since 2×118517681² = 28092881419235522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (118517881) 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, 1911545 + ... + 1911606.

It is an arithmetic number, because the mean of its divisors is an integer number (30585216).

Almost surely, 2^118517681 is an apocalyptic number.

It is an amenable number.

118517681 is a deficient number, since it is larger than the sum of its proper divisors (3823183).

118517681 is an equidigital number, since it uses as much as digits as its factorization.

118517681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3823182.

The product of its digits is 13440, while the sum is 38.

The square root of 118517681 is about 10886.5826134743. The cubic root of 118517681 is about 491.2030427743.

The spelling of 118517681 in words is "one hundred eighteen million, five hundred seventeen thousand, six hundred eighty-one".