6866 has 4 divisors (see below), whose sum is σ = 10302. Its totient is φ = 3432.

The previous prime is 6863. The next prime is 6869. The reversal of 6866 is 6686.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 6686 = 2 ⋅3343.

It is an interprime number because it is at equal distance from previous prime (6863) and next prime (6869).

It can be written as a sum of positive squares in only one way, i.e., 6241 + 625 = 79^2 + 25^2 .

It is not an unprimeable number, because it can be changed into a prime (6863) 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 as a sum of consecutive naturals, namely, 1715 + ... + 1718.

2⁶⁸⁶⁶ is an apocalyptic number.

6866 is a deficient number, since it is larger than the sum of its proper divisors (3436).

6866 is a wasteful number, since it uses less digits than its factorization.

6866 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3435.

The product of its digits is 1728, while the sum is 26.

The square root of 6866 is about 82.8613299435. The cubic root of 6866 is about 19.0064613297.

The spelling of 6866 in words is "six thousand, eight hundred sixty-six".