991326600 has 240 divisors, whose sum is σ = 3756701520. Its totient is φ = 240278400.

The previous prime is 991326599. The next prime is 991326613. The reversal of 991326600 is 6623199.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 59 ways as a sum of consecutive naturals, for example, 175419 + ... + 180981.

It is an arithmetic number, because the mean of its divisors is an integer number (15652923).

Almost surely, 2^991326600 is an apocalyptic number.

991326600 is a gapful number since it is divisible by the number (90) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 991326600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1878350760).

991326600 is an abundant number, since it is smaller than the sum of its proper divisors (2765374920).

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

991326600 is a wasteful number, since it uses less digits than its factorization.

991326600 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5602 (or 5584 counting only the distinct ones).

The product of its (nonzero) digits is 17496, while the sum is 36.

The square root of 991326600 is about 31485.3394455261. The cubic root of 991326600 is about 997.1004675037.

Adding to 991326600 its reverse (6623199), we get a palindrome (997949799).

The spelling of 991326600 in words is "nine hundred ninety-one million, three hundred twenty-six thousand, six hundred".