189665409 has 32 divisors (see below), whose sum is σ = 269824000. Its totient is φ = 118324800.

The previous prime is 189665401. The next prime is 189665419. The reversal of 189665409 is 904566981.

It is not a de Polignac number, because 189665409 - 2³ = 189665401 is a prime.

It is a super-2 number, since 2×189665409² = 71945934742274562, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (189665401) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 379842 + ... + 380340.

It is an arithmetic number, because the mean of its divisors is an integer number (8432000).

Almost surely, 2^189665409 is an apocalyptic number.

It is an amenable number.

189665409 is a deficient number, since it is larger than the sum of its proper divisors (80158591).

189665409 is a wasteful number, since it uses less digits than its factorization.

189665409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 661.

The product of its (nonzero) digits is 466560, while the sum is 48.

The square root of 189665409 is about 13771.9065128979. The cubic root of 189665409 is about 574.5520483430.

The spelling of 189665409 in words is "one hundred eighty-nine million, six hundred sixty-five thousand, four hundred nine".