66814734691 has 2 divisors, whose sum is σ = 66814734692. Its totient is φ = 66814734690.

The previous prime is 66814734667. The next prime is 66814734709. The reversal of 66814734691 is 19643741866.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 66814734691 - 2¹³ = 66814726499 is a prime.

It is not a weakly prime, because it can be changed into another prime (66814734661) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33407367345 + 33407367346.

It is an arithmetic number, because the mean of its divisors is an integer number (33407367346).

Almost surely, 2^66814734691 is an apocalyptic number.

66814734691 is a deficient number, since it is larger than the sum of its proper divisors (1).

66814734691 is an equidigital number, since it uses as much as digits as its factorization.

66814734691 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5225472, while the sum is 55.

The spelling of 66814734691 in words is "sixty-six billion, eight hundred fourteen million, seven hundred thirty-four thousand, six hundred ninety-one".