1285651 has 4 divisors (see below), whose sum is σ = 1288872. Its totient is φ = 1282432.

The previous prime is 1285649. The next prime is 1285679. The reversal of 1285651 is 1565821.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1285651 - 2¹ = 1285649 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1285051) 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, 910 + ... + 1843.

It is an arithmetic number, because the mean of its divisors is an integer number (322218).

2^1285651 is an apocalyptic number.

1285651 is a deficient number, since it is larger than the sum of its proper divisors (3221).

1285651 is an equidigital number, since it uses as much as digits as its factorization.

1285651 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3220.

The product of its digits is 2400, while the sum is 28.

The square root of 1285651 is about 1133.8655123073. The cubic root of 1285651 is about 108.7362531617.

It can be divided in two parts, 1285 and 651, that added together give a square (1936 = 44²).

The spelling of 1285651 in words is "one million, two hundred eighty-five thousand, six hundred fifty-one".