991626199 has 2 divisors, whose sum is σ = 991626200. Its totient is φ = 991626198.

The previous prime is 991626179. The next prime is 991626227.

991626199 is nontrivially palindromic in base 10.

It is a weak prime.

It is a palprime.

It is a cyclic number.

It is not a de Polignac number, because 991626199 - 2¹⁹ = 991101911 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (991626179) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 495813099 + 495813100.

It is an arithmetic number, because the mean of its divisors is an integer number (495813100).

Almost surely, 2^991626199 is an apocalyptic number.

991626199 is a deficient number, since it is larger than the sum of its proper divisors (1).

991626199 is an equidigital number, since it uses as much as digits as its factorization.

991626199 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 472392, while the sum is 52.

The square root of 991626199 is about 31490.0968401178. The cubic root of 991626199 is about 997.2009053795.

The spelling of 991626199 in words is "nine hundred ninety-one million, six hundred twenty-six thousand, one hundred ninety-nine".