991875 has 30 divisors (see below), whose sum is σ = 1727572. Its totient is φ = 506000.

The previous prime is 991873. The next prime is 991883. The reversal of 991875 is 578199.

It is a happy number.

It is not a de Polignac number, because 991875 - 2¹ = 991873 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 991875.

It is not an unprimeable number, because it can be changed into a prime (991871) by changing a digit.

It is a polite number, since it can be written in 29 ways as a sum of consecutive naturals, for example, 43114 + ... + 43136.

2⁹⁹¹⁸⁷⁵ is an apocalyptic number.

991875 is a deficient number, since it is larger than the sum of its proper divisors (735697).

991875 is an equidigital number, since it uses as much as digits as its factorization.

991875 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 69 (or 31 counting only the distinct ones).

The product of its digits is 22680, while the sum is 39.

The square root of 991875 is about 995.9292143521. The cubic root of 991875 is about 99.7284298307.

The spelling of 991875 in words is "nine hundred ninety-one thousand, eight hundred seventy-five".