66566612237 has 2 divisors, whose sum is σ = 66566612238. Its totient is φ = 66566612236.

The previous prime is 66566612191. The next prime is 66566612317. The reversal of 66566612237 is 73221666566.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 54503104681 + 12063507556 = 233459^2 + 109834^2 .

It is a cyclic number.

It is not a de Polignac number, because 66566612237 - 2¹⁸ = 66566350093 is a prime.

It is a super-2 number, since 2×66566612237² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66566612137) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33283306118 + 33283306119.

It is an arithmetic number, because the mean of its divisors is an integer number (33283306119).

Almost surely, 2^66566612237 is an apocalyptic number.

It is an amenable number.

66566612237 is a deficient number, since it is larger than the sum of its proper divisors (1).

66566612237 is an equidigital number, since it uses as much as digits as its factorization.

66566612237 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3265920, while the sum is 50.

The spelling of 66566612237 in words is "sixty-six billion, five hundred sixty-six million, six hundred twelve thousand, two hundred thirty-seven".