66655470691 has 2 divisors, whose sum is σ = 66655470692. Its totient is φ = 66655470690.

The previous prime is 66655470683. The next prime is 66655470701. The reversal of 66655470691 is 19607455666.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 66655470691 - 2³ = 66655470683 is a prime.

It is not a weakly prime, because it can be changed into another prime (66655470631) 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 as a sum of consecutive naturals, namely, 33327735345 + 33327735346.

It is an arithmetic number, because the mean of its divisors is an integer number (33327735346).

Almost surely, 2^66655470691 is an apocalyptic number.

66655470691 is a deficient number, since it is larger than the sum of its proper divisors (1).

66655470691 is an equidigital number, since it uses as much as digits as its factorization.

66655470691 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8164800, while the sum is 55.

The spelling of 66655470691 in words is "sixty-six billion, six hundred fifty-five million, four hundred seventy thousand, six hundred ninety-one".