6897691 has 2 divisors, whose sum is σ = 6897692. Its totient is φ = 6897690.

The previous prime is 6897689. The next prime is 6897719. The reversal of 6897691 is 1967986.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 6897691 - 2¹ = 6897689 is a prime.

It is a super-2 number, since 2×6897691² = 95156282262962, which contains 22 as substring.

Together with 6897689, it forms a pair of twin primes.

6897691 is a lucky number.

It is not a weakly prime, because it can be changed into another prime (6897641) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3448845 + 3448846.

It is an arithmetic number, because the mean of its divisors is an integer number (3448846).

Almost surely, 2^6897691 is an apocalyptic number.

6897691 is a deficient number, since it is larger than the sum of its proper divisors (1).

6897691 is an equidigital number, since it uses as much as digits as its factorization.

6897691 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 163296, while the sum is 46.

The square root of 6897691 is about 2626.3455598988. The cubic root of 6897691 is about 190.3565879623.

The spelling of 6897691 in words is "six million, eight hundred ninety-seven thousand, six hundred ninety-one".