188681 has 2 divisors, whose sum is σ = 188682. Its totient is φ = 188680.

The previous prime is 188677. The next prime is 188687. The reversal of 188681 is 186881.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 173056 + 15625 = 416^2 + 125^2 .

It is a cyclic number.

It is not a de Polignac number, because 188681 - 2² = 188677 is a prime.

It is a super-2 number, since 2×188681² = 71201039522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (188687) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 94340 + 94341.

It is an arithmetic number, because the mean of its divisors is an integer number (94341).

2¹⁸⁸⁶⁸¹ is an apocalyptic number.

It is an amenable number.

188681 is a deficient number, since it is larger than the sum of its proper divisors (1).

188681 is an equidigital number, since it uses as much as digits as its factorization.

188681 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3072, while the sum is 32.

The square root of 188681 is about 434.3742625893. The cubic root of 188681 is about 57.3556302616.

The spelling of 188681 in words is "one hundred eighty-eight thousand, six hundred eighty-one".