991673743879 has 96 divisors (see below), whose sum is σ = 1367013580800. Its totient is φ = 710220026880.

The previous prime is 991673743867. The next prime is 991673743891. The reversal of 991673743879 is 978347376199.

It is an interprime number because it is at equal distance from previous prime (991673743867) and next prime (991673743891).

It is not a de Polignac number, because 991673743879 - 2⁵ = 991673743847 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (991673743279) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 29623519 + ... + 29656975.

It is an arithmetic number, because the mean of its divisors is an integer number (14239724800).

Almost surely, 2^991673743879 is an apocalyptic number.

991673743879 is a deficient number, since it is larger than the sum of its proper divisors (375339836921).

991673743879 is a wasteful number, since it uses less digits than its factorization.

991673743879 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33613 (or 33606 counting only the distinct ones).

The product of its digits is 432081216, while the sum is 73.

The spelling of 991673743879 in words is "nine hundred ninety-one billion, six hundred seventy-three million, seven hundred forty-three thousand, eight hundred seventy-nine".