991259 has 8 divisors (see below), whose sum is σ = 1030320. Its totient is φ = 953056.

The previous prime is 991229. The next prime is 991261. The reversal of 991259 is 952199.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-991259 is a prime.

It is not an unprimeable number, because it can be changed into a prime (991229) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2969 + ... + 3285.

It is an arithmetic number, because the mean of its divisors is an integer number (128790).

2⁹⁹¹²⁵⁹ is an apocalyptic number.

991259 is a deficient number, since it is larger than the sum of its proper divisors (39061).

991259 is a wasteful number, since it uses less digits than its factorization.

991259 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 429.

The product of its digits is 7290, while the sum is 35.

The square root of 991259 is about 995.6199073944. The cubic root of 991259 is about 99.7077802412.

Subtracting from 991259 its reverse (952199), we obtain a triangular number (39060 = T₂₇₉).

The spelling of 991259 in words is "nine hundred ninety-one thousand, two hundred fifty-nine".