189780165 has 20 divisors (see below), whose sum is σ = 340199244. Its totient is φ = 101215872.

The previous prime is 189780161. The next prime is 189780193. The reversal of 189780165 is 561087981.

It can be written as a sum of positive squares in 2 ways, for example, as 81162081 + 108618084 = 9009^2 + 10422^2 .

It is not a de Polignac number, because 189780165 - 2² = 189780161 is a prime.

It is a super-2 number, since 2×189780165² = 72033022054854450, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 189780165.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (189780161) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 233892 + ... + 234701.

Almost surely, 2^189780165 is an apocalyptic number.

189780165 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

189780165 is a deficient number, since it is larger than the sum of its proper divisors (150419079).

189780165 is an equidigital number, since it uses as much as digits as its factorization.

189780165 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 468610 (or 468601 counting only the distinct ones).

The product of its (nonzero) digits is 120960, while the sum is 45.

The square root of 189780165 is about 13776.0721905774. The cubic root of 189780165 is about 574.6679014870.

The spelling of 189780165 in words is "one hundred eighty-nine million, seven hundred eighty thousand, one hundred sixty-five".