991193250 has 64 divisors (see below), whose sum is σ = 2505484800. Its totient is φ = 260956800.

The previous prime is 991193249. The next prime is 991193309. The reversal of 991193250 is 52391199.

It is a junction number, because it is equal to n+sod(n) for n = 991193199 and 991193208.

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 31 ways as a sum of consecutive naturals, for example, 50886 + ... + 67614.

It is an arithmetic number, because the mean of its divisors is an integer number (39148200).

Almost surely, 2^991193250 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 991193250, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1252742400).

991193250 is an abundant number, since it is smaller than the sum of its proper divisors (1514291550).

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

991193250 is a wasteful number, since it uses less digits than its factorization.

991193250 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16828 (or 16818 counting only the distinct ones).

The product of its (nonzero) digits is 21870, while the sum is 39.

The square root of 991193250 is about 31483.2217220538. The cubic root of 991193250 is about 997.0557566050.

The spelling of 991193250 in words is "nine hundred ninety-one million, one hundred ninety-three thousand, two hundred fifty".