1285664 has 12 divisors (see below), whose sum is σ = 2531214. Its totient is φ = 642816.

The previous prime is 1285649. The next prime is 1285679. The reversal of 1285664 is 4665821.

It is an interprime number because it is at equal distance from previous prime (1285649) and next prime (1285679).

It can be written as a sum of positive squares in only one way, i.e., 795664 + 490000 = 892^2 + 700^2 .

It is a Harshad number since it is a multiple of its sum of digits (32), and also a Moran number because the ratio is a prime number: 40177 = 1285664 / (1 + 2 + 8 + 5 + 6 + 6 + 4).

It is a self number, because there is not a number n which added to its sum of digits gives 1285664.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20057 + ... + 20120.

2^1285664 is an apocalyptic number.

It is an amenable number.

1285664 is a deficient number, since it is larger than the sum of its proper divisors (1245550).

1285664 is an equidigital number, since it uses as much as digits as its factorization.

1285664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40187 (or 40179 counting only the distinct ones).

The product of its digits is 11520, while the sum is 32.

The square root of 1285664 is about 1133.8712448951. The cubic root of 1285664 is about 108.7366196600.

The spelling of 1285664 in words is "one million, two hundred eighty-five thousand, six hundred sixty-four".