66612566473 has 2 divisors, whose sum is σ = 66612566474. Its totient is φ = 66612566472.

The previous prime is 66612566459. The next prime is 66612566513. The reversal of 66612566473 is 37466521666.

66612566473 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 54789701184 + 11822865289 = 234072^2 + 108733^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66612566473 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 66612566473.

It is not a weakly prime, because it can be changed into another prime (66612566173) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33306283236 + 33306283237.

It is an arithmetic number, because the mean of its divisors is an integer number (33306283237).

Almost surely, 2^66612566473 is an apocalyptic number.

It is an amenable number.

66612566473 is a deficient number, since it is larger than the sum of its proper divisors (1).

66612566473 is an equidigital number, since it uses as much as digits as its factorization.

66612566473 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6531840, while the sum is 52.

The spelling of 66612566473 in words is "sixty-six billion, six hundred twelve million, five hundred sixty-six thousand, four hundred seventy-three".