991767199 has 16 divisors (see below), whose sum is σ = 1099839168. Its totient is φ = 889523712.

The previous prime is 991767193. The next prime is 991767211.

991767199 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 991767199 - 2³ = 991767191 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (991767191) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 103729 + ... + 112885.

It is an arithmetic number, because the mean of its divisors is an integer number (68739948).

Almost surely, 2^991767199 is an apocalyptic number.

991767199 is a deficient number, since it is larger than the sum of its proper divisors (108071969).

991767199 is a wasteful number, since it uses less digits than its factorization.

991767199 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9474.

The product of its digits is 1928934, while the sum is 58.

The square root of 991767199 is about 31492.3355596247. The cubic root of 991767199 is about 997.2481673633.

The spelling of 991767199 in words is "nine hundred ninety-one million, seven hundred sixty-seven thousand, one hundred ninety-nine".