6816663 has 16 divisors (see below), whose sum is σ = 11541760. Its totient is φ = 3895128.

The previous prime is 6816659. The next prime is 6816679. The reversal of 6816663 is 3666186.

It is not a de Polignac number, because 6816663 - 2² = 6816659 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 (6816613) 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, 17845 + ... + 18222.

It is an arithmetic number, because the mean of its divisors is an integer number (721360).

Almost surely, 2^6816663 is an apocalyptic number.

6816663 is a gapful number since it is divisible by the number (63) formed by its first and last digit.

6816663 is a deficient number, since it is larger than the sum of its proper divisors (4725097).

6816663 is a wasteful number, since it uses less digits than its factorization.

6816663 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36083 (or 36077 counting only the distinct ones).

The product of its digits is 31104, while the sum is 36.

The square root of 6816663 is about 2610.8739915974. The cubic root of 6816663 is about 189.6082695480.

The spelling of 6816663 in words is "six million, eight hundred sixteen thousand, six hundred sixty-three".