991098368 has 160 divisors (see below), whose sum is σ = 2382035040. Its totient is φ = 406978560.

The previous prime is 991098337. The next prime is 991098389. The reversal of 991098368 is 863890199.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2149658 + ... + 2150118.

It is an arithmetic number, because the mean of its divisors is an integer number (14887719).

Almost surely, 2^991098368 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 991098368, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1191017520).

991098368 is an abundant number, since it is smaller than the sum of its proper divisors (1390936672).

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

991098368 is a wasteful number, since it uses less digits than its factorization.

991098368 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 528 (or 512 counting only the distinct ones).

The product of its (nonzero) digits is 839808, while the sum is 53.

The square root of 991098368 is about 31481.7148198760. The cubic root of 991098368 is about 997.0239411936.

The spelling of 991098368 in words is "nine hundred ninety-one million, ninety-eight thousand, three hundred sixty-eight".