165617172 has 72 divisors (see below), whose sum is σ = 481225472. Its totient is φ = 47044800.

The previous prime is 165617171. The next prime is 165617183. The reversal of 165617172 is 271716561.

It is a super-2 number, since 2×165617172² = 54858095322555168, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165617171) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 43797 + ... + 47427.

Almost surely, 2^165617172 is an apocalyptic number.

165617172 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 165617172, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (240612736).

165617172 is an abundant number, since it is smaller than the sum of its proper divisors (315608300).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

165617172 is a wasteful number, since it uses less digits than its factorization.

165617172 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3829 (or 3824 counting only the distinct ones).

The product of its digits is 17640, while the sum is 36.

The square root of 165617172 is about 12869.2335436109. The cubic root of 165617172 is about 549.1636567045.

The spelling of 165617172 in words is "one hundred sixty-five million, six hundred seventeen thousand, one hundred seventy-two".