189816961 has 2 divisors, whose sum is σ = 189816962. Its totient is φ = 189816960.

The previous prime is 189816941. The next prime is 189816997. The reversal of 189816961 is 169618981.

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., 186486336 + 3330625 = 13656^2 + 1825^2 .It is also a bemirp because it and its reverse can be mirrored producing other two distinct primes, 196918681 and 186819691.

It is a cyclic number.

It is not a de Polignac number, because 189816961 - 2⁹ = 189816449 is a prime.

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

It is not a weakly prime, because it can be changed into another prime (189816901) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 94908480 + 94908481.

It is an arithmetic number, because the mean of its divisors is an integer number (94908481).

Almost surely, 2^189816961 is an apocalyptic number.

It is an amenable number.

189816961 is a deficient number, since it is larger than the sum of its proper divisors (1).

189816961 is an equidigital number, since it uses as much as digits as its factorization.

189816961 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 186624, while the sum is 49.

The square root of 189816961 is about 13777.4076298845. The cubic root of 189816961 is about 574.7050393927.

The spelling of 189816961 in words is "one hundred eighty-nine million, eight hundred sixteen thousand, nine hundred sixty-one".