189323981 has 24 divisors (see below), whose sum is σ = 240166080. Its totient is φ = 146076480.

The previous prime is 189323957. The next prime is 189323989.

189323981 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 189323981 - 2²⁶ = 122215117 is a prime.

It is a super-2 number, since 2×189323981² = 71687139563376722, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (189323989) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 89585 + ... + 91673.

It is an arithmetic number, because the mean of its divisors is an integer number (10006920).

Almost surely, 2^189323981 is an apocalyptic number.

189323981 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

189323981 is a deficient number, since it is larger than the sum of its proper divisors (50842099).

189323981 is a wasteful number, since it uses less digits than its factorization.

189323981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2225 (or 2214 counting only the distinct ones).

The product of its digits is 93312, while the sum is 44.

The square root of 189323981 is about 13759.5051146471. The cubic root of 189323981 is about 574.2070794721.

The spelling of 189323981 in words is "one hundred eighty-nine million, three hundred twenty-three thousand, nine hundred eighty-one".