6691115213 has 2 divisors, whose sum is σ = 6691115214. Its totient is φ = 6691115212.

The previous prime is 6691115203. The next prime is 6691115231. The reversal of 6691115213 is 3125111966.

Together with next prime (6691115231) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 5786188489 + 904926724 = 76067^2 + 30082^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-6691115213 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6691115203) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3345557606 + 3345557607.

It is an arithmetic number, because the mean of its divisors is an integer number (3345557607).

Almost surely, 2^6691115213 is an apocalyptic number.

It is an amenable number.

6691115213 is a deficient number, since it is larger than the sum of its proper divisors (1).

6691115213 is an equidigital number, since it uses as much as digits as its factorization.

6691115213 is an evil number, because the sum of its binary digits is even.

The product of its digits is 9720, while the sum is 35.

The square root of 6691115213 is about 81799.2372397200. The cubic root of 6691115213 is about 1884.3699473394.

The spelling of 6691115213 in words is "six billion, six hundred ninety-one million, one hundred fifteen thousand, two hundred thirteen".