6787681 has 4 divisors (see below), whose sum is σ = 6825364. Its totient is φ = 6750000.

The previous prime is 6787663. The next prime is 6787699. The reversal of 6787681 is 1867876.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (6787663) and next prime (6787699).

It can be written as a sum of positive squares in 2 ways, for example, as 950625 + 5837056 = 975^2 + 2416^2 .

It is a 6-Lehmer number, since φ(6787681) divides (6787681-1)⁶.

It is a cyclic number.

It is not a de Polignac number, because 6787681 - 2¹⁹ = 6263393 is a prime.

It is a super-2 number, since 2×6787681² = 92145226715522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6787631) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 18570 + ... + 18931.

It is an arithmetic number, because the mean of its divisors is an integer number (1706341).

Almost surely, 2^6787681 is an apocalyptic number.

It is an amenable number.

6787681 is a deficient number, since it is larger than the sum of its proper divisors (37683).

6787681 is a wasteful number, since it uses less digits than its factorization.

6787681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37682.

The product of its digits is 112896, while the sum is 43.

The square root of 6787681 is about 2605.3178308989. The cubic root of 6787681 is about 189.3391724240.

The spelling of 6787681 in words is "six million, seven hundred eighty-seven thousand, six hundred eighty-one".