999917189 has 2 divisors, whose sum is σ = 999917190. Its totient is φ = 999917188.

The previous prime is 999917137. The next prime is 999917207. The reversal of 999917189 is 981719999.

999917189 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 637966564 + 361950625 = 25258^2 + 19025^2 .

It is a cyclic number.

It is not a de Polignac number, because 999917189 - 2²⁸ = 731481733 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (999917089) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 499958594 + 499958595.

It is an arithmetic number, because the mean of its divisors is an integer number (499958595).

Almost surely, 2^999917189 is an apocalyptic number.

It is an amenable number.

999917189 is a deficient number, since it is larger than the sum of its proper divisors (1).

999917189 is an equidigital number, since it uses as much as digits as its factorization.

999917189 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3306744, while the sum is 62.

The square root of 999917189 is about 31621.4672176988. The cubic root of 999917189 is about 999.9723955713.

The spelling of 999917189 in words is "nine hundred ninety-nine million, nine hundred seventeen thousand, one hundred eighty-nine".