991380183 has 8 divisors (see below), whose sum is σ = 1357565808. Its totient is φ = 643057344.

The previous prime is 991380163. The next prime is 991380193. The reversal of 991380183 is 381083199.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 991380183 - 2²⁰ = 990331607 is a prime.

It is a super-2 number, since 2×991380183² = 1965669334490226978, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (991380163) 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 in 7 ways as a sum of consecutive naturals, for example, 4465566 + ... + 4465787.

It is an arithmetic number, because the mean of its divisors is an integer number (169695726).

Almost surely, 2^991380183 is an apocalyptic number.

991380183 is a deficient number, since it is larger than the sum of its proper divisors (366185625).

991380183 is a wasteful number, since it uses less digits than its factorization.

991380183 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8931393.

The product of its (nonzero) digits is 46656, while the sum is 42.

The square root of 991380183 is about 31486.1903538678. The cubic root of 991380183 is about 997.1184322094.

The spelling of 991380183 in words is "nine hundred ninety-one million, three hundred eighty thousand, one hundred eighty-three".