6861691 has 2 divisors, whose sum is σ = 6861692. Its totient is φ = 6861690.

The previous prime is 6861629. The next prime is 6861697. The reversal of 6861691 is 1961686.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 6861691 - 2¹⁹ = 6337403 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 6861691.

It is not a weakly prime, because it can be changed into another prime (6861697) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3430845 + 3430846.

It is an arithmetic number, because the mean of its divisors is an integer number (3430846).

Almost surely, 2^6861691 is an apocalyptic number.

6861691 is a deficient number, since it is larger than the sum of its proper divisors (1).

6861691 is an equidigital number, since it uses as much as digits as its factorization.

6861691 is an evil number, because the sum of its binary digits is even.

The product of its digits is 15552, while the sum is 37.

The square root of 6861691 is about 2619.4829642508. The cubic root of 6861691 is about 190.0248443966.

The spelling of 6861691 in words is "six million, eight hundred sixty-one thousand, six hundred ninety-one".