6691555751 has 2 divisors, whose sum is σ = 6691555752. Its totient is φ = 6691555750.

The previous prime is 6691555733. The next prime is 6691555817. The reversal of 6691555751 is 1575551966.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 6691555751 - 2⁶ = 6691555687 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 6691555751.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6691555711) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3345777875 + 3345777876.

It is an arithmetic number, because the mean of its divisors is an integer number (3345777876).

Almost surely, 2^6691555751 is an apocalyptic number.

6691555751 is a deficient number, since it is larger than the sum of its proper divisors (1).

6691555751 is an equidigital number, since it uses as much as digits as its factorization.

6691555751 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1417500, while the sum is 50.

The square root of 6691555751 is about 81801.9299955692. The cubic root of 6691555751 is about 1884.4113015992.

The spelling of 6691555751 in words is "six billion, six hundred ninety-one million, five hundred fifty-five thousand, seven hundred fifty-one".