6691497251 has 2 divisors, whose sum is σ = 6691497252. Its totient is φ = 6691497250.

The previous prime is 6691497223. The next prime is 6691497259. The reversal of 6691497251 is 1527941966.

6691497251 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 6691497251 - 2⁶ = 6691497187 is a prime.

It is a super-2 number, since 2×6691497251² = 89552270920281114002, which contains 22 as substring.

It is a Sophie Germain prime.

It is a self number, because there is not a number n which added to its sum of digits gives 6691497251.

It is not a weakly prime, because it can be changed into another prime (6691497259) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3345748625 + 3345748626.

It is an arithmetic number, because the mean of its divisors is an integer number (3345748626).

Almost surely, 2^6691497251 is an apocalyptic number.

6691497251 is a deficient number, since it is larger than the sum of its proper divisors (1).

6691497251 is an equidigital number, since it uses as much as digits as its factorization.

6691497251 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 816480, while the sum is 50.

The square root of 6691497251 is about 81801.5724237621. The cubic root of 6691497251 is about 1884.4058101815.

The spelling of 6691497251 in words is "six billion, six hundred ninety-one million, four hundred ninety-seven thousand, two hundred fifty-one".