165910891 has 8 divisors (see below), whose sum is σ = 176060160. Its totient is φ = 156006312.

The previous prime is 165910867. The next prime is 165910903. The reversal of 165910891 is 198019561.

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

It is a cyclic number.

It is not a de Polignac number, because 165910891 - 2⁵ = 165910859 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (165950891) 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, 59775 + ... + 62488.

It is an arithmetic number, because the mean of its divisors is an integer number (22007520).

Almost surely, 2^165910891 is an apocalyptic number.

165910891 is a deficient number, since it is larger than the sum of its proper divisors (10149269).

165910891 is a wasteful number, since it uses less digits than its factorization.

165910891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 122345.

The product of its (nonzero) digits is 19440, while the sum is 40.

The square root of 165910891 is about 12880.6401626627. The cubic root of 165910891 is about 549.4881088490.

The spelling of 165910891 in words is "one hundred sixty-five million, nine hundred ten thousand, eight hundred ninety-one".