189681 has 8 divisors (see below), whose sum is σ = 264000. Its totient is φ = 120912.

The previous prime is 189671. The next prime is 189691. The reversal of 189681 is 186981.

It is an interprime number because it is at equal distance from previous prime (189671) and next prime (189691).

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

It is not a de Polignac number, because 189681 - 2⁶ = 189617 is a prime.

It is a super-2 number, since 2×189681² = 71957763522, which contains 22 as substring.

189681 is a strobogrammatic number because it is the same when read upside-down.

It is not an unprimeable number, because it can be changed into a prime (189661) 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, 1306 + ... + 1443.

It is an arithmetic number, because the mean of its divisors is an integer number (33000).

2¹⁸⁹⁶⁸¹ is an apocalyptic number.

It is an amenable number.

189681 is a deficient number, since it is larger than the sum of its proper divisors (74319).

189681 is a wasteful number, since it uses less digits than its factorization.

189681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2775.

The product of its digits is 3456, while the sum is 33.

The square root of 189681 is about 435.5238225402. The cubic root of 189681 is about 57.4567791146.

The spelling of 189681 in words is "one hundred eighty-nine thousand, six hundred eighty-one".