6699 has 16 divisors (see below), whose sum is σ = 11520. Its totient is φ = 3360.

The previous prime is 6691. The next prime is 6701. The reversal of 6699 is 9966.

6699 = T₃₄ + T₃₅ + ... + T₄₂.

6699 = 15² + 16² + ... + 28².

It is not a de Polignac number, because 6699 - 2³ = 6691 is a prime.

6699 is a strobogrammatic number because it is the same when read upside-down.

6699 is a modest number, since divided by 99 gives 66 as remainder.

It is a plaindrome in base 10.

It is a zygodrome in base 10.

It is not an unprimeable number, because it can be changed into a prime (6691) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 217 + ... + 245.

It is an arithmetic number, because the mean of its divisors is an integer number (720).

2⁶⁶⁹⁹ is an apocalyptic number.

6699 is a deficient number, since it is larger than the sum of its proper divisors (4821).

6699 is a wasteful number, since it uses less digits than its factorization.

6699 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50.

The product of its digits is 2916, while the sum is 30.

The square root of 6699 is about 81.8474190186. The cubic root of 6699 is about 18.8510983513.

The spelling of 6699 in words is "six thousand, six hundred ninety-nine".