189391903 has 2 divisors, whose sum is σ = 189391904. Its totient is φ = 189391902.

The previous prime is 189391879. The next prime is 189391919. The reversal of 189391903 is 309193981.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 189391903 - 2²⁵ = 155837471 is a prime.

It is a super-2 number, since 2×189391903² = 71738585843922818, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 189391903.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (189391933) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 94695951 + 94695952.

It is an arithmetic number, because the mean of its divisors is an integer number (94695952).

Almost surely, 2^189391903 is an apocalyptic number.

189391903 is a deficient number, since it is larger than the sum of its proper divisors (1).

189391903 is an equidigital number, since it uses as much as digits as its factorization.

189391903 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 52488, while the sum is 43.

The square root of 189391903 is about 13761.9730780146. The cubic root of 189391903 is about 574.2757389026.

The spelling of 189391903 in words is "one hundred eighty-nine million, three hundred ninety-one thousand, nine hundred three".