189920871 has 12 divisors (see below), whose sum is σ = 313520272. Its totient is φ = 108526176.

The previous prime is 189920869. The next prime is 189920933. The reversal of 189920871 is 178029981.

It is not a de Polignac number, because 189920871 - 2¹ = 189920869 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (189920831) by changing a digit.

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 11 ways as a sum of consecutive naturals, for example, 1507246 + ... + 1507371.

Almost surely, 2^189920871 is an apocalyptic number.

189920871 is a deficient number, since it is larger than the sum of its proper divisors (123599401).

189920871 is a wasteful number, since it uses less digits than its factorization.

189920871 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3014630 (or 3014627 counting only the distinct ones).

The product of its (nonzero) digits is 72576, while the sum is 45.

The square root of 189920871 is about 13781.1781426698. The cubic root of 189920871 is about 574.8098890098.

The spelling of 189920871 in words is "one hundred eighty-nine million, nine hundred twenty thousand, eight hundred seventy-one".