189905646 has 32 divisors (see below), whose sum is σ = 456917760. Its totient is φ = 51402816.

The previous prime is 189905609. The next prime is 189905699. The reversal of 189905646 is 646509981.

It is a junction number, because it is equal to n+sod(n) for n = 189905595 and 189905604.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 118191 + ... + 119786.

It is an arithmetic number, because the mean of its divisors is an integer number (14278680).

Almost surely, 2^189905646 is an apocalyptic number.

189905646 is an abundant number, since it is smaller than the sum of its proper divisors (267012114).

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

189905646 is a wasteful number, since it uses less digits than its factorization.

189905646 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 238008.

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

The square root of 189905646 is about 13780.6257477663. The cubic root of 189905646 is about 574.7945287278.

The spelling of 189905646 in words is "one hundred eighty-nine million, nine hundred five thousand, six hundred forty-six".