1287705 has 8 divisors (see below), whose sum is σ = 2060352. Its totient is φ = 686768.

The previous prime is 1287697. The next prime is 1287707. The reversal of 1287705 is 5077821.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 1287705 - 2³ = 1287697 is a prime.

It is a Curzon number.

It is a nialpdrome in base 6.

It is not an unprimeable number, because it can be changed into a prime (1287707) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 42909 + ... + 42938.

It is an arithmetic number, because the mean of its divisors is an integer number (257544).

2^1287705 is an apocalyptic number.

1287705 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1287705 is a deficient number, since it is larger than the sum of its proper divisors (772647).

1287705 is an equidigital number, since it uses as much as digits as its factorization.

1287705 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 85855.

The product of its (nonzero) digits is 3920, while the sum is 30.

The square root of 1287705 is about 1134.7709019886. The cubic root of 1287705 is about 108.7941292698.

The spelling of 1287705 in words is "one million, two hundred eighty-seven thousand, seven hundred five".