6687881 has 2 divisors, whose sum is σ = 6687882. Its totient is φ = 6687880.

The previous prime is 6687869. The next prime is 6687931. The reversal of 6687881 is 1887866.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 6175225 + 512656 = 2485^2 + 716^2 .

It is a cyclic number.

It is not a de Polignac number, because 6687881 - 2¹⁰ = 6686857 is a prime.

It is a super-2 number, since 2×6687881² = 89455504540322, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (6687781) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3343940 + 3343941.

It is an arithmetic number, because the mean of its divisors is an integer number (3343941).

Almost surely, 2^6687881 is an apocalyptic number.

It is an amenable number.

6687881 is a deficient number, since it is larger than the sum of its proper divisors (1).

6687881 is an equidigital number, since it uses as much as digits as its factorization.

6687881 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 129024, while the sum is 44.

The square root of 6687881 is about 2586.0937724684. The cubic root of 6687881 is about 188.4066289141.

The spelling of 6687881 in words is "six million, six hundred eighty-seven thousand, eight hundred eighty-one".