66662217 has 8 divisors (see below), whose sum is σ = 98758880. Its totient is φ = 44441460.

The previous prime is 66662209. The next prime is 66662221. The reversal of 66662217 is 71226666.

It is not a de Polignac number, because 66662217 - 2³ = 66662209 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66662207) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1234459 + ... + 1234512.

It is an arithmetic number, because the mean of its divisors is an integer number (12344860).

Almost surely, 2^66662217 is an apocalyptic number.

It is an amenable number.

66662217 is a deficient number, since it is larger than the sum of its proper divisors (32096663).

66662217 is a wasteful number, since it uses less digits than its factorization.

66662217 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2468980 (or 2468974 counting only the distinct ones).

The product of its digits is 36288, while the sum is 36.

The square root of 66662217 is about 8164.6933194089. The cubic root of 66662217 is about 405.4711115804.

The spelling of 66662217 in words is "sixty-six million, six hundred sixty-two thousand, two hundred seventeen".