165561155 has 16 divisors (see below), whose sum is σ = 209690400. Its totient is φ = 125141760.

The previous prime is 165561131. The next prime is 165561233. The reversal of 165561155 is 551165561.

165561155 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 165561155 - 2⁶ = 165561091 is a prime.

It is a super-3 number, since 3×165561155³ (a number of 26 digits) contains 333 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 36725 + ... + 40985.

It is an arithmetic number, because the mean of its divisors is an integer number (13105650).

Almost surely, 2^165561155 is an apocalyptic number.

165561155 is a deficient number, since it is larger than the sum of its proper divisors (44129245).

165561155 is a wasteful number, since it uses less digits than its factorization.

165561155 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4694.

The product of its digits is 22500, while the sum is 35.

The square root of 165561155 is about 12867.0569673100. The cubic root of 165561155 is about 549.1017348455.

The spelling of 165561155 in words is "one hundred sixty-five million, five hundred sixty-one thousand, one hundred fifty-five".