161518159 has 4 divisors (see below), whose sum is σ = 176201640. Its totient is φ = 146834680.

The previous prime is 161518141. The next prime is 161518169. The reversal of 161518159 is 951815161.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 161518159 - 2¹⁹ = 160993871 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161518129) 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, 7341724 + ... + 7341745.

It is an arithmetic number, because the mean of its divisors is an integer number (44050410).

Almost surely, 2^161518159 is an apocalyptic number.

161518159 is a deficient number, since it is larger than the sum of its proper divisors (14683481).

161518159 is a wasteful number, since it uses less digits than its factorization.

161518159 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14683480.

The product of its digits is 10800, while the sum is 37.

The square root of 161518159 is about 12708.9794633558. The cubic root of 161518159 is about 544.5951700032.

It can be divided in two parts, 16151 and 8159, that added together give a triangular number (24310 = T₂₂₀).

The spelling of 161518159 in words is "one hundred sixty-one million, five hundred eighteen thousand, one hundred fifty-nine".