66404619 has 6 divisors (see below), whose sum is σ = 95917796. Its totient is φ = 44269740.

The previous prime is 66404593. The next prime is 66404623. The reversal of 66404619 is 91640466.

66404619 is a `hidden beast` number, since 6 + 640 + 4 + 6 + 1 + 9 = 666.

66404619 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 66404619 - 2¹⁷ = 66273547 is a prime.

It is a super-2 number, since 2×66404619² = 8819146849070322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66404629) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3689137 + ... + 3689154.

Almost surely, 2^66404619 is an apocalyptic number.

66404619 is a deficient number, since it is larger than the sum of its proper divisors (29513177).

66404619 is a wasteful number, since it uses less digits than its factorization.

66404619 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7378297 (or 7378294 counting only the distinct ones).

The product of its (nonzero) digits is 31104, while the sum is 36.

The square root of 66404619 is about 8148.9029322971. The cubic root of 66404619 is about 404.9481598028.

The spelling of 66404619 in words is "sixty-six million, four hundred four thousand, six hundred nineteen".