66840804059 has 4 divisors (see below), whose sum is σ = 66841331400. Its totient is φ = 66840276720.

The previous prime is 66840804053. The next prime is 66840804067. The reversal of 66840804059 is 95040804866.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66840804059 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 66840803998 and 66840804016.

It is not an unprimeable number, because it can be changed into a prime (66840804053) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 54167 + ... + 369615.

It is an arithmetic number, because the mean of its divisors is an integer number (16710332850).

Almost surely, 2^66840804059 is an apocalyptic number.

66840804059 is a deficient number, since it is larger than the sum of its proper divisors (527341).

66840804059 is a wasteful number, since it uses less digits than its factorization.

66840804059 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 527340.

The product of its (nonzero) digits is 1658880, while the sum is 50.

The spelling of 66840804059 in words is "sixty-six billion, eight hundred forty million, eight hundred four thousand, fifty-nine".