6687997801 has 2 divisors, whose sum is σ = 6687997802. Its totient is φ = 6687997800.

The previous prime is 6687997787. The next prime is 6687997847. The reversal of 6687997801 is 1087997866.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 3972024576 + 2715973225 = 63024^2 + 52115^2 .

It is a cyclic number.

It is not a de Polignac number, because 6687997801 - 2¹⁵ = 6687965033 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 6687997801.

It is not a weakly prime, because it can be changed into another prime (6687997501) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3343998900 + 3343998901.

It is an arithmetic number, because the mean of its divisors is an integer number (3343998901).

Almost surely, 2^6687997801 is an apocalyptic number.

It is an amenable number.

6687997801 is a deficient number, since it is larger than the sum of its proper divisors (1).

6687997801 is an equidigital number, since it uses as much as digits as its factorization.

6687997801 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 9144576, while the sum is 61.

The square root of 6687997801 is about 81780.1797564667. The cubic root of 6687997801 is about 1884.0772572158.

The spelling of 6687997801 in words is "six billion, six hundred eighty-seven million, nine hundred ninety-seven thousand, eight hundred one".