1287686 has 8 divisors (see below), whose sum is σ = 1936440. Its totient is φ = 642208.

The previous prime is 1287683. The next prime is 1287691. The reversal of 1287686 is 6867821.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1287683) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 830 + ... + 1806.

It is an arithmetic number, because the mean of its divisors is an integer number (242055).

2^1287686 is an apocalyptic number.

1287686 is a deficient number, since it is larger than the sum of its proper divisors (648754).

1287686 is an equidigital number, since it uses as much as digits as its factorization.

1287686 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1638.

The product of its digits is 32256, while the sum is 38.

The square root of 1287686 is about 1134.7625302238. The cubic root of 1287686 is about 108.7935941838.

The spelling of 1287686 in words is "one million, two hundred eighty-seven thousand, six hundred eighty-six".