66408219 has 6 divisors (see below), whose sum is σ = 95922996. Its totient is φ = 44272140.

The previous prime is 66408203. The next prime is 66408253. The reversal of 66408219 is 91280466.

66408219 is a `hidden beast` number, since 6 + 640 + 8 + 2 + 1 + 9 = 666.

It is not a de Polignac number, because 66408219 - 2⁴ = 66408203 is a prime.

It is a super-2 number, since 2×66408219² = 8820103101503922, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (66408619) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3689337 + ... + 3689354.

It is an arithmetic number, because the mean of its divisors is an integer number (15987166).

Almost surely, 2^66408219 is an apocalyptic number.

66408219 is a deficient number, since it is larger than the sum of its proper divisors (29514777).

66408219 is a wasteful number, since it uses less digits than its factorization.

66408219 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7378697 (or 7378694 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 36.

The square root of 66408219 is about 8149.1238179328. The cubic root of 66408219 is about 404.9554775017.

The spelling of 66408219 in words is "sixty-six million, four hundred eight thousand, two hundred nineteen".