6641999873 has 2 divisors, whose sum is σ = 6641999874. Its totient is φ = 6641999872.

The previous prime is 6641999863. The next prime is 6641999951. The reversal of 6641999873 is 3789991466.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 5819858944 + 822140929 = 76288^2 + 28673^2 .

It is a cyclic number.

It is not a de Polignac number, because 6641999873 - 2⁶ = 6641999809 is a prime.

It is a super-2 number, since 2×6641999873² = 88232324625864032258, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (6641999843) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3320999936 + 3320999937.

It is an arithmetic number, because the mean of its divisors is an integer number (3320999937).

Almost surely, 2^6641999873 is an apocalyptic number.

It is an amenable number.

6641999873 is a deficient number, since it is larger than the sum of its proper divisors (1).

6641999873 is an equidigital number, since it uses as much as digits as its factorization.

6641999873 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 17635968, while the sum is 62.

The square root of 6641999873 is about 81498.4654640810. The cubic root of 6641999873 is about 1879.7479548368.

The spelling of 6641999873 in words is "six billion, six hundred forty-one million, nine hundred ninety-nine thousand, eight hundred seventy-three".