6985681 has 2 divisors, whose sum is σ = 6985682. Its totient is φ = 6985680.

The previous prime is 6985679. The next prime is 6985687. The reversal of 6985681 is 1865896.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 6838225 + 147456 = 2615^2 + 384^2 .

It is a cyclic number.

It is not a de Polignac number, because 6985681 - 2¹ = 6985679 is a prime.

It is a super-2 number, since 2×6985681² = 97599478067522, which contains 22 as substring.

Together with 6985679, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (6985687) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3492840 + 3492841.

It is an arithmetic number, because the mean of its divisors is an integer number (3492841).

Almost surely, 2^6985681 is an apocalyptic number.

It is an amenable number.

6985681 is a deficient number, since it is larger than the sum of its proper divisors (1).

6985681 is an equidigital number, since it uses as much as digits as its factorization.

6985681 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 103680, while the sum is 43.

The square root of 6985681 is about 2643.0438891551. The cubic root of 6985681 is about 191.1625946592.

The spelling of 6985681 in words is "six million, nine hundred eighty-five thousand, six hundred eighty-one".