66375217 has 12 divisors (see below), whose sum is σ = 69793024. Its totient is φ = 63118440.

The previous prime is 66375173. The next prime is 66375251. The reversal of 66375217 is 71257366.

It is not a de Polignac number, because 66375217 - 2¹⁹ = 65850929 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66375277) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 143128 + ... + 143590.

Almost surely, 2^66375217 is an apocalyptic number.

It is an amenable number.

66375217 is a deficient number, since it is larger than the sum of its proper divisors (3417807).

66375217 is a wasteful number, since it uses less digits than its factorization.

66375217 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 780 (or 757 counting only the distinct ones).

The product of its digits is 52920, while the sum is 37.

The square root of 66375217 is about 8147.0986860354. The cubic root of 66375217 is about 404.8883846262. Note that the first 3 decimals are identical.

The spelling of 66375217 in words is "sixty-six million, three hundred seventy-five thousand, two hundred seventeen".