1005865 has 16 divisors (see below), whose sum is σ = 1428480. Its totient is φ = 665280.

The previous prime is 1005833. The next prime is 1005883. The reversal of 1005865 is 5685001.

It is not a de Polignac number, because 1005865 - 2⁵ = 1005833 is a prime.

1005865 is a lucky number.

It is an unprimeable 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 15 ways as a sum of consecutive naturals, for example, 520 + ... + 1510.

It is an arithmetic number, because the mean of its divisors is an integer number (89280).

2^1005865 is an apocalyptic number.

It is an amenable number.

1005865 is a deficient number, since it is larger than the sum of its proper divisors (422615).

1005865 is an equidigital number, since it uses as much as digits as its factorization.

1005865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1032.

The product of its (nonzero) digits is 1200, while the sum is 25.

The square root of 1005865 is about 1002.9282127849. The cubic root of 1005865 is about 100.1951190380.

The spelling of 1005865 in words is "one million, five thousand, eight hundred sixty-five".