66681671443 has 2 divisors, whose sum is σ = 66681671444. Its totient is φ = 66681671442.

The previous prime is 66681671417. The next prime is 66681671453. The reversal of 66681671443 is 34417618666.

66681671443 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 66681671443 - 2⁵ = 66681671411 is a prime.

It is not a weakly prime, because it can be changed into another prime (66681671453) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33340835721 + 33340835722.

It is an arithmetic number, because the mean of its divisors is an integer number (33340835722).

Almost surely, 2^66681671443 is an apocalyptic number.

66681671443 is a deficient number, since it is larger than the sum of its proper divisors (1).

66681671443 is an equidigital number, since it uses as much as digits as its factorization.

66681671443 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3483648, while the sum is 52.

The spelling of 66681671443 in words is "sixty-six billion, six hundred eighty-one million, six hundred seventy-one thousand, four hundred forty-three".