66419217 has 16 divisors (see below), whose sum is σ = 98949760. Its totient is φ = 44031600.

The previous prime is 66419209. The next prime is 66419233. The reversal of 66419217 is 71291466.

66419217 is a `hidden beast` number, since 6 + 641 + 9 + 2 + 1 + 7 = 666.

It is not a de Polignac number, because 66419217 - 2³ = 66419209 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66419207) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1909 + ... + 11682.

It is an arithmetic number, because the mean of its divisors is an integer number (6184360).

Almost surely, 2^66419217 is an apocalyptic number.

It is an amenable number.

66419217 is a deficient number, since it is larger than the sum of its proper divisors (32530543).

66419217 is a wasteful number, since it uses less digits than its factorization.

66419217 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13781 (or 13775 counting only the distinct ones).

The product of its digits is 18144, while the sum is 36.

The square root of 66419217 is about 8149.7985864683. The cubic root of 66419217 is about 404.9778314340.

It can be divided in two parts, 664 and 19217, that added together give a square (19881 = 141²).

The spelling of 66419217 in words is "sixty-six million, four hundred nineteen thousand, two hundred seventeen".