6621688873 has 2 divisors, whose sum is σ = 6621688874. Its totient is φ = 6621688872.

The previous prime is 6621688867. The next prime is 6621688903. The reversal of 6621688873 is 3788861266.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 6310236969 + 311451904 = 79437^2 + 17648^2 .

It is a cyclic number.

It is not a de Polignac number, because 6621688873 - 2¹⁷ = 6621557801 is a prime.

It is not a weakly prime, because it can be changed into another prime (6621688373) 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, 3310844436 + 3310844437.

It is an arithmetic number, because the mean of its divisors is an integer number (3310844437).

Almost surely, 2^6621688873 is an apocalyptic number.

It is an amenable number.

6621688873 is a deficient number, since it is larger than the sum of its proper divisors (1).

6621688873 is an equidigital number, since it uses as much as digits as its factorization.

6621688873 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4644864, while the sum is 55.

The square root of 6621688873 is about 81373.7603469325. The cubic root of 6621688873 is about 1877.8299309012.

The spelling of 6621688873 in words is "six billion, six hundred twenty-one million, six hundred eighty-eight thousand, eight hundred seventy-three".