189836891 has 2 divisors, whose sum is σ = 189836892. Its totient is φ = 189836890.

The previous prime is 189836863. The next prime is 189836903. The reversal of 189836891 is 198638981.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 189836891 - 2²⁶ = 122728027 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (189836821) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 94918445 + 94918446.

It is an arithmetic number, because the mean of its divisors is an integer number (94918446).

Almost surely, 2^189836891 is an apocalyptic number.

189836891 is a deficient number, since it is larger than the sum of its proper divisors (1).

189836891 is an equidigital number, since it uses as much as digits as its factorization.

189836891 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 746496, while the sum is 53.

The square root of 189836891 is about 13778.1308964605. The cubic root of 189836891 is about 574.7251525770.

The spelling of 189836891 in words is "one hundred eighty-nine million, eight hundred thirty-six thousand, eight hundred ninety-one".