189911867 has 2 divisors, whose sum is σ = 189911868. Its totient is φ = 189911866.

The previous prime is 189911833. The next prime is 189911881. The reversal of 189911867 is 768119981.

It is a strong prime.

It is an emirp because it is prime and its reverse (768119981) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 189911867 - 2²⁰ = 188863291 is a prime.

It is not a weakly prime, because it can be changed into another prime (189911167) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 94955933 + 94955934.

It is an arithmetic number, because the mean of its divisors is an integer number (94955934).

Almost surely, 2^189911867 is an apocalyptic number.

189911867 is a deficient number, since it is larger than the sum of its proper divisors (1).

189911867 is an equidigital number, since it uses as much as digits as its factorization.

189911867 is an evil number, because the sum of its binary digits is even.

The product of its digits is 217728, while the sum is 50.

The square root of 189911867 is about 13780.8514613575. The cubic root of 189911867 is about 574.8008051038.

The spelling of 189911867 in words is "one hundred eighty-nine million, nine hundred eleven thousand, eight hundred sixty-seven".