991089376 has 24 divisors (see below), whose sum is σ = 1992725280. Its totient is φ = 485000448.

The previous prime is 991089361. The next prime is 991089377. The reversal of 991089376 is 673980199.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (991089377) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 327981 + ... + 330988.

It is an arithmetic number, because the mean of its divisors is an integer number (83030220).

Almost surely, 2^991089376 is an apocalyptic number.

It is an amenable number.

991089376 is an abundant number, since it is smaller than the sum of its proper divisors (1001635904).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

991089376 is a wasteful number, since it uses less digits than its factorization.

991089376 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 659026 (or 659018 counting only the distinct ones).

The product of its (nonzero) digits is 734832, while the sum is 52.

The square root of 991089376 is about 31481.5720064929. The cubic root of 991089376 is about 997.0209259307.

The spelling of 991089376 in words is "nine hundred ninety-one million, eighty-nine thousand, three hundred seventy-six".