991065 has 8 divisors (see below), whose sum is σ = 1585728. Its totient is φ = 528560.

The previous prime is 991063. The next prime is 991069. The reversal of 991065 is 560199.

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

It is not a de Polignac number, because 991065 - 2¹ = 991063 is a prime.

It is not an unprimeable number, because it can be changed into a prime (991063) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 33021 + ... + 33050.

It is an arithmetic number, because the mean of its divisors is an integer number (198216).

2⁹⁹¹⁰⁶⁵ is an apocalyptic number.

It is an amenable number.

991065 is a deficient number, since it is larger than the sum of its proper divisors (594663).

991065 is a wasteful number, since it uses less digits than its factorization.

991065 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66079.

The product of its (nonzero) digits is 2430, while the sum is 30.

The square root of 991065 is about 995.5224758889. The cubic root of 991065 is about 99.7012751901.

The spelling of 991065 in words is "nine hundred ninety-one thousand, sixty-five".