1099 has 4 divisors (see below), whose sum is σ = 1264.
Its totient is φ = 936.
The previous prime is 1097. The next prime is 1103. The reversal of 1099 is 9901.
It can be divided in two parts, 10 and 99, that multiplied together give a triangular number (990 = T44).
1099 is nontrivially palindromic in base 12 and base 15.
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 1099 - 21 = 1097 is a prime.
It is a Duffinian number.
1099 is an undulating number in base 15.
1099 is a modest number, since divided by 99 gives 10 as remainder.
1099 is a nontrivial repdigit in base 12.
It is a plaindrome in base 5, base 12, base 13 and base 16.
It is a nialpdrome in base 12.
It is a zygodrome in base 12.
It is not an unprimeable number, because it can be changed into a prime (1091) by changing a digit.
It is a pernicious number, because its binary representation contains a prime number (5) of ones.
It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 72 + ... + 85.
It is an arithmetic number, because the mean of its divisors is an integer number (316).
1099 is a deficient number, since it is larger than the sum of its proper divisors (165).
1099 is an equidigital number, since it uses as much as digits as its factorization.
1099 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 164.
The product of its (nonzero) digits is 81, while the sum is 19.
The square root of 1099 is about 33.1511689085.
The cubic root of 1099 is about 10.3196720846.
The spelling of 1099 in words is "one thousand, ninety-nine".