66445617 has 32 divisors (see below), whose sum is σ = 106700800. Its totient is φ = 36726480.

The previous prime is 66445591. The next prime is 66445627. The reversal of 66445617 is 71654466.

It is not a de Polignac number, because 66445617 - 2⁶ = 66445553 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66445627) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 30858 + ... + 32940.

It is an arithmetic number, because the mean of its divisors is an integer number (3334400).

Almost surely, 2^66445617 is an apocalyptic number.

It is an amenable number.

66445617 is a deficient number, since it is larger than the sum of its proper divisors (40255183).

66445617 is a wasteful number, since it uses less digits than its factorization.

66445617 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2138 (or 2124 counting only the distinct ones).

The product of its digits is 120960, while the sum is 39.

The square root of 66445617 is about 8151.4180974846. The cubic root of 66445617 is about 405.0314805586.

The spelling of 66445617 in words is "sixty-six million, four hundred forty-five thousand, six hundred seventeen".