865897 has 4 divisors (see below), whose sum is σ = 869760. Its totient is φ = 862036.

The previous prime is 865889. The next prime is 865933. The reversal of 865897 is 798568.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 865897 - 2³ = 865889 is a prime.

It is a super-2 number, since 2×865897² = 1499555229218, which contains 22 as substring.

It is a Duffinian number.

865897 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (865807) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1573 + ... + 2050.

It is an arithmetic number, because the mean of its divisors is an integer number (217440).

2⁸⁶⁵⁸⁹⁷ is an apocalyptic number.

It is an amenable number.

865897 is a deficient number, since it is larger than the sum of its proper divisors (3863).

865897 is a wasteful number, since it uses less digits than its factorization.

865897 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3862.

The product of its digits is 120960, while the sum is 43.

The square root of 865897 is about 930.5358671217. The cubic root of 865897 is about 95.3137181785.

The spelling of 865897 in words is "eight hundred sixty-five thousand, eight hundred ninety-seven".