189628561 has 2 divisors, whose sum is σ = 189628562. Its totient is φ = 189628560.

The previous prime is 189628507. The next prime is 189628601. The reversal of 189628561 is 165826981.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 188897536 + 731025 = 13744^2 + 855^2 .

It is an emirp because it is prime and its reverse (165826981) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 189628561 - 2¹⁵ = 189595793 is a prime.

It is a super-2 number, since 2×189628561² = 71917982293861442, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (189628661) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 94814280 + 94814281.

It is an arithmetic number, because the mean of its divisors is an integer number (94814281).

Almost surely, 2^189628561 is an apocalyptic number.

It is an amenable number.

189628561 is a deficient number, since it is larger than the sum of its proper divisors (1).

189628561 is an equidigital number, since it uses as much as digits as its factorization.

189628561 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 207360, while the sum is 46.

The square root of 189628561 is about 13770.5686520201. The cubic root of 189628561 is about 574.5148381401.

The spelling of 189628561 in words is "one hundred eighty-nine million, six hundred twenty-eight thousand, five hundred sixty-one".