997865 has 8 divisors (see below), whose sum is σ = 1306368. Its totient is φ = 725680.

The previous prime is 997813. The next prime is 997877. The reversal of 997865 is 568799.

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

It is not a de Polignac number, because 997865 - 2⁸ = 997609 is a prime.

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 997865.

It is an unprimeable number.

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, 9017 + ... + 9126.

It is an arithmetic number, because the mean of its divisors is an integer number (163296).

2⁹⁹⁷⁸⁶⁵ is an apocalyptic number.

It is an amenable number.

997865 is a deficient number, since it is larger than the sum of its proper divisors (308503).

997865 is a wasteful number, since it uses less digits than its factorization.

997865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18159.

The product of its digits is 136080, while the sum is 44.

The square root of 997865 is about 998.9319296128. The cubic root of 997865 is about 99.9287826262.

The spelling of 997865 in words is "nine hundred ninety-seven thousand, eight hundred sixty-five".