6641171813 has 2 divisors, whose sum is σ = 6641171814. Its totient is φ = 6641171812.

The previous prime is 6641171807. The next prime is 6641171879. The reversal of 6641171813 is 3181711466.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 5806135204 + 835036609 = 76198^2 + 28897^2 .

It is a cyclic number.

It is not a de Polignac number, because 6641171813 - 2⁸ = 6641171557 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6641171113) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3320585906 + 3320585907.

It is an arithmetic number, because the mean of its divisors is an integer number (3320585907).

Almost surely, 2^6641171813 is an apocalyptic number.

It is an amenable number.

6641171813 is a deficient number, since it is larger than the sum of its proper divisors (1).

6641171813 is an equidigital number, since it uses as much as digits as its factorization.

6641171813 is an evil number, because the sum of its binary digits is even.

The product of its digits is 24192, while the sum is 38.

The square root of 6641171813 is about 81493.3850873799. The cubic root of 6641171813 is about 1879.6698353541.

The spelling of 6641171813 in words is "six billion, six hundred forty-one million, one hundred seventy-one thousand, eight hundred thirteen".