991330 has 8 divisors (see below), whose sum is σ = 1784412. Its totient is φ = 396528.

The previous prime is 991327. The next prime is 991343. The reversal of 991330 is 33199.

It can be written as a sum of positive squares in 2 ways, for example, as 974169 + 17161 = 987^2 + 131^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a junction number, because it is equal to n+sod(n) for n = 991295 and 991304.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 49557 + ... + 49576.

2⁹⁹¹³³⁰ is an apocalyptic number.

991330 is a deficient number, since it is larger than the sum of its proper divisors (793082).

991330 is a wasteful number, since it uses less digits than its factorization.

991330 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 99140.

The product of its (nonzero) digits is 729, while the sum is 25.

The square root of 991330 is about 995.6555629333. The cubic root of 991330 is about 99.7101607437.

The spelling of 991330 in words is "nine hundred ninety-one thousand, three hundred thirty".