865628 has 18 divisors (see below), whose sum is σ = 1597176. Its totient is φ = 409728.

The previous prime is 865619. The next prime is 865637. The reversal of 865628 is 826568.

It is an interprime number because it is at equal distance from previous prime (865619) and next prime (865637).

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 865628.

It is an unprimeable number.

865628 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

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 5 ways as a sum of consecutive naturals, for example, 8876 + ... + 8972.

It is an arithmetic number, because the mean of its divisors is an integer number (88732).

2⁸⁶⁵⁶²⁸ is an apocalyptic number.

It is an amenable number.

865628 is a deficient number, since it is larger than the sum of its proper divisors (731548).

865628 is a wasteful number, since it uses less digits than its factorization.

865628 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 221 (or 122 counting only the distinct ones).

The product of its digits is 23040, while the sum is 35.

The square root of 865628 is about 930.3913155227. The cubic root of 865628 is about 95.3038470869.

Subtracting from 865628 its reverse (826568), we obtain a triangular number (39060 = T₂₇₉).

The spelling of 865628 in words is "eight hundred sixty-five thousand, six hundred twenty-eight".