66840914165 has 16 divisors (see below), whose sum is σ = 80815529088. Its totient is φ = 53069445696.

The previous prime is 66840914149. The next prime is 66840914167. The reversal of 66840914165 is 56141904866.

66840914165 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is not a de Polignac number, because 66840914165 - 2⁴ = 66840914149 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66840914167) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 474659 + ... + 599151.

It is an arithmetic number, because the mean of its divisors is an integer number (5050970568).

Almost surely, 2^66840914165 is an apocalyptic number.

It is an amenable number.

66840914165 is a deficient number, since it is larger than the sum of its proper divisors (13974614923).

66840914165 is a wasteful number, since it uses less digits than its factorization.

66840914165 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 125308.

The product of its (nonzero) digits is 1244160, while the sum is 50.

The spelling of 66840914165 in words is "sixty-six billion, eight hundred forty million, nine hundred fourteen thousand, one hundred sixty-five".