1287699 has 16 divisors (see below), whose sum is σ = 2078208. Its totient is φ = 692352.

The previous prime is 1287697. The next prime is 1287707. The reversal of 1287699 is 9967821.

It is not a de Polignac number, because 1287699 - 2¹ = 1287697 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1287699.

It is not an unprimeable number, because it can be changed into a prime (1287691) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1447 + ... + 2160.

It is an arithmetic number, because the mean of its divisors is an integer number (129888).

2^1287699 is an apocalyptic number.

1287699 is a deficient number, since it is larger than the sum of its proper divisors (790509).

1287699 is a wasteful number, since it uses less digits than its factorization.

1287699 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3634.

The product of its digits is 54432, while the sum is 42.

The square root of 1287699 is about 1134.7682582801. The cubic root of 1287699 is about 108.7939602959.

It can be divided in two parts, 128769 and 9, that added together give a triangular number (128778 = T₅₀₇).

The spelling of 1287699 in words is "one million, two hundred eighty-seven thousand, six hundred ninety-nine".