66840804067 has 2 divisors, whose sum is σ = 66840804068. Its totient is φ = 66840804066.

The previous prime is 66840804053. The next prime is 66840804073. The reversal of 66840804067 is 76040804866.

66840804067 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 66840804067 - 2²⁷ = 66706586339 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 66840804067.

It is not a weakly prime, because it can be changed into another prime (66840814067) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33420402033 + 33420402034.

It is an arithmetic number, because the mean of its divisors is an integer number (33420402034).

Almost surely, 2^66840804067 is an apocalyptic number.

66840804067 is a deficient number, since it is larger than the sum of its proper divisors (1).

66840804067 is an equidigital number, since it uses as much as digits as its factorization.

66840804067 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1548288, while the sum is 49.

The spelling of 66840804067 in words is "sixty-six billion, eight hundred forty million, eight hundred four thousand, sixty-seven".