18791161 has 8 divisors (see below), whose sum is σ = 20087424. Its totient is φ = 17534880.

The previous prime is 18791147. The next prime is 18791167. The reversal of 18791161 is 16119781.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 18791161 - 2²¹ = 16694009 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18791167) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9021 + ... + 10906.

It is an arithmetic number, because the mean of its divisors is an integer number (2510928).

Almost surely, 2^18791161 is an apocalyptic number.

It is an amenable number.

18791161 is a deficient number, since it is larger than the sum of its proper divisors (1296263).

18791161 is a wasteful number, since it uses less digits than its factorization.

18791161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19991.

The product of its digits is 3024, while the sum is 34.

The square root of 18791161 is about 4334.8772762329. The cubic root of 18791161 is about 265.8589006134.

The spelling of 18791161 in words is "eighteen million, seven hundred ninety-one thousand, one hundred sixty-one".