66277217 has 2 divisors, whose sum is σ = 66277218. Its totient is φ = 66277216.

The previous prime is 66277201. The next prime is 66277229. The reversal of 66277217 is 71277266.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 63856081 + 2421136 = 7991^2 + 1556^2 .

It is a cyclic number.

It is not a de Polignac number, because 66277217 - 2⁴ = 66277201 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (66277297) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33138608 + 33138609.

It is an arithmetic number, because the mean of its divisors is an integer number (33138609).

Almost surely, 2^66277217 is an apocalyptic number.

It is an amenable number.

66277217 is a deficient number, since it is larger than the sum of its proper divisors (1).

66277217 is an equidigital number, since it uses as much as digits as its factorization.

66277217 is an evil number, because the sum of its binary digits is even.

The product of its digits is 49392, while the sum is 38.

The square root of 66277217 is about 8141.0820533882. The cubic root of 66277217 is about 404.6890200258.

The spelling of 66277217 in words is "sixty-six million, two hundred seventy-seven thousand, two hundred seventeen".