1087999 has 4 divisors (see below), whose sum is σ = 1186920. Its totient is φ = 989080.

The previous prime is 1087987. The next prime is 1088023. The reversal of 1087999 is 9997801.

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 1087999 - 2⁵ = 1087967 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1087799) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 49444 + ... + 49465.

It is an arithmetic number, because the mean of its divisors is an integer number (296730).

2^1087999 is an apocalyptic number.

1087999 is a deficient number, since it is larger than the sum of its proper divisors (98921).

1087999 is an equidigital number, since it uses as much as digits as its factorization.

1087999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 98920.

The product of its (nonzero) digits is 40824, while the sum is 43.

The square root of 1087999 is about 1043.0719054792. The cubic root of 1087999 is about 102.8512321155.

The spelling of 1087999 in words is "one million, eighty-seven thousand, nine hundred ninety-nine".