189172305 has 48 divisors (see below), whose sum is σ = 384893184. Its totient is φ = 84136320.

The previous prime is 189172297. The next prime is 189172327. The reversal of 189172305 is 503271981.

189172305 is a `hidden beast` number, since 189 + 172 + 305 = 666.

It is not a de Polignac number, because 189172305 - 2³ = 189172297 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 189172305.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 3540 + ... + 19770.

It is an arithmetic number, because the mean of its divisors is an integer number (8018608).

Almost surely, 2^189172305 is an apocalyptic number.

189172305 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

189172305 is an abundant number, since it is smaller than the sum of its proper divisors (195720879).

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

189172305 is a wasteful number, since it uses less digits than its factorization.

189172305 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16286 (or 16283 counting only the distinct ones).

The product of its (nonzero) digits is 15120, while the sum is 36.

The square root of 189172305 is about 13753.9923295020. The cubic root of 189172305 is about 574.0536974212.

The spelling of 189172305 in words is "one hundred eighty-nine million, one hundred seventy-two thousand, three hundred five".