991100169 has 12 divisors (see below), whose sum is σ = 1431935856. Its totient is φ = 660573432.

The previous prime is 991100141. The next prime is 991100179. The reversal of 991100169 is 961001199.

It is not a de Polignac number, because 991100169 - 2⁵ = 991100137 is a prime.

It is a super-2 number, since 2×991100169² = 1964559089983657122, which contains 22 as substring.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (991100179) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 35182 + ... + 56744.

It is an arithmetic number, because the mean of its divisors is an integer number (119327988).

Almost surely, 2^991100169 is an apocalyptic number.

It is an amenable number.

991100169 is a deficient number, since it is larger than the sum of its proper divisors (440835687).

991100169 is a wasteful number, since it uses less digits than its factorization.

991100169 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26676 (or 26673 counting only the distinct ones).

The product of its (nonzero) digits is 4374, while the sum is 36.

The square root of 991100169 is about 31481.7434237686. The cubic root of 991100169 is about 997.0245451158.

The spelling of 991100169 in words is "nine hundred ninety-one million, one hundred thousand, one hundred sixty-nine".