1115999 has 4 divisors (see below), whose sum is σ = 1181664. Its totient is φ = 1050336.

The previous prime is 1115993. The next prime is 1116001. The reversal of 1115999 is 9995111.

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 1115999 - 2⁸ = 1115743 is a prime.

It is a Duffinian number.

It is a plaindrome in base 10 and base 12.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1115993) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is an upside-down number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 32807 + ... + 32840.

It is an arithmetic number, because the mean of its divisors is an integer number (295416).

2^1115999 is an apocalyptic number.

1115999 is a deficient number, since it is larger than the sum of its proper divisors (65665).

1115999 is an equidigital number, since it uses as much as digits as its factorization.

1115999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65664.

The product of its digits is 3645, while the sum is 35.

The square root of 1115999 is about 1056.4085383979. The cubic root of 1115999 is about 103.7260727713.

The spelling of 1115999 in words is "one million, one hundred fifteen thousand, nine hundred ninety-nine".