189272981 has 4 divisors (see below), whose sum is σ = 189325152. Its totient is φ = 189220812.

The previous prime is 189272969. The next prime is 189272983.

189272981 is nontrivially palindromic in base 10.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-189272981 is a prime.

It is a super-2 number, since 2×189272981² = 71648522673252722, which contains 22 as substring.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (189272983) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20201 + ... + 28046.

It is an arithmetic number, because the mean of its divisors is an integer number (47331288).

Almost surely, 2^189272981 is an apocalyptic number.

It is an amenable number.

189272981 is a deficient number, since it is larger than the sum of its proper divisors (52171).

189272981 is an equidigital number, since it uses as much as digits as its factorization.

189272981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52170.

The product of its digits is 145152, while the sum is 47.

The square root of 189272981 is about 13757.6517254944. The cubic root of 189272981 is about 574.1555149691.

The spelling of 189272981 in words is "one hundred eighty-nine million, two hundred seventy-two thousand, nine hundred eighty-one".