991235 has 16 divisors (see below), whose sum is σ = 1376256. Its totient is φ = 671328.

The previous prime is 991229. The next prime is 991261. The reversal of 991235 is 532199.

It is not a de Polignac number, because 991235 - 2⁶ = 991171 is a prime.

It is a Smith number, since the sum of its digits (29) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a junction number, because it is equal to n+sod(n) for n = 991198 and 991207.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4334 + ... + 4556.

It is an arithmetic number, because the mean of its divisors is an integer number (86016).

2⁹⁹¹²³⁵ is an apocalyptic number.

991235 is a deficient number, since it is larger than the sum of its proper divisors (385021).

991235 is a wasteful number, since it uses less digits than its factorization.

991235 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 362.

The product of its digits is 2430, while the sum is 29.

The square root of 991235 is about 995.6078545291. The cubic root of 991235 is about 99.7069755387.

It can be divided in two parts, 99 and 1235, that multiplied together give a triangular number (122265 = T₄₉₄).

The spelling of 991235 in words is "nine hundred ninety-one thousand, two hundred thirty-five".