189921019 has 2 divisors, whose sum is σ = 189921020. Its totient is φ = 189921018.

The previous prime is 189921013. The next prime is 189921047. The reversal of 189921019 is 910129981.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 189921019 - 2¹⁷ = 189789947 is a prime.

It is a super-2 number, since 2×189921019² = 72139986915996722, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (189921013) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 94960509 + 94960510.

It is an arithmetic number, because the mean of its divisors is an integer number (94960510).

Almost surely, 2^189921019 is an apocalyptic number.

189921019 is a deficient number, since it is larger than the sum of its proper divisors (1).

189921019 is an equidigital number, since it uses as much as digits as its factorization.

189921019 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 11664, while the sum is 40.

The square root of 189921019 is about 13781.1835123113. The cubic root of 189921019 is about 574.8100383208.

The spelling of 189921019 in words is "one hundred eighty-nine million, nine hundred twenty-one thousand, nineteen".