189636981 has 8 divisors (see below), whose sum is σ = 253016544. Its totient is φ = 126341040.

The previous prime is 189636973. The next prime is 189637039.

189636981 is nontrivially palindromic in base 10.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 189636981 - 2³ = 189636973 is a prime.

It is a super-2 number, since 2×189636981² = 71924369125588722, which contains 22 as substring.

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

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (189636901) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15406 + ... + 24831.

It is an arithmetic number, because the mean of its divisors is an integer number (31627068).

Almost surely, 2^189636981 is an apocalyptic number.

It is an amenable number.

189636981 is a deficient number, since it is larger than the sum of its proper divisors (63379563).

189636981 is a wasteful number, since it uses less digits than its factorization.

189636981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41811.

The product of its digits is 559872, while the sum is 51.

The square root of 189636981 is about 13770.8743731108. The cubic root of 189636981 is about 574.5233413306.

The spelling of 189636981 in words is "one hundred eighty-nine million, six hundred thirty-six thousand, nine hundred eighty-one".