991528199 has 2 divisors, whose sum is σ = 991528200. Its totient is φ = 991528198.

The previous prime is 991528193. The next prime is 991528207. The reversal of 991528199 is 991825199.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 991528199 - 2¹² = 991524103 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 991528199.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (991528193) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 495764099 + 495764100.

It is an arithmetic number, because the mean of its divisors is an integer number (495764100).

Almost surely, 2^991528199 is an apocalyptic number.

991528199 is a deficient number, since it is larger than the sum of its proper divisors (1).

991528199 is an equidigital number, since it uses as much as digits as its factorization.

991528199 is an evil number, because the sum of its binary digits is even.

The product of its digits is 524880, while the sum is 53.

The square root of 991528199 is about 31488.5407569166. The cubic root of 991528199 is about 997.1680539858.

The spelling of 991528199 in words is "nine hundred ninety-one million, five hundred twenty-eight thousand, one hundred ninety-nine".