6366541681 has 2 divisors, whose sum is σ = 6366541682. Its totient is φ = 6366541680.

The previous prime is 6366541663. The next prime is 6366541711. The reversal of 6366541681 is 1861456636.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 4448890000 + 1917651681 = 66700^2 + 43791^2 .

It is a cyclic number.

It is not a de Polignac number, because 6366541681 - 2⁹ = 6366541169 is a prime.

It is a super-2 number, since 2×6366541681² = 81065705951820611522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (6366541081) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3183270840 + 3183270841.

It is an arithmetic number, because the mean of its divisors is an integer number (3183270841).

Almost surely, 2^6366541681 is an apocalyptic number.

It is an amenable number.

6366541681 is a deficient number, since it is larger than the sum of its proper divisors (1).

6366541681 is an equidigital number, since it uses as much as digits as its factorization.

6366541681 is an evil number, because the sum of its binary digits is even.

The product of its digits is 622080, while the sum is 46.

The square root of 6366541681 is about 79790.6114840587. The cubic root of 6366541681 is about 1853.3944672533.

The spelling of 6366541681 in words is "six billion, three hundred sixty-six million, five hundred forty-one thousand, six hundred eighty-one".