66419643 has 4 divisors (see below), whose sum is σ = 88559528. Its totient is φ = 44279760.

The previous prime is 66419623. The next prime is 66419651. The reversal of 66419643 is 34691466.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 66419643 - 2¹⁶ = 66354107 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66419623) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11069938 + ... + 11069943.

It is an arithmetic number, because the mean of its divisors is an integer number (22139882).

Almost surely, 2^66419643 is an apocalyptic number.

66419643 is a deficient number, since it is larger than the sum of its proper divisors (22139885).

66419643 is a wasteful number, since it uses less digits than its factorization.

66419643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22139884.

The product of its digits is 93312, while the sum is 39.

The square root of 66419643 is about 8149.8247220416. The cubic root of 66419643 is about 404.9786972487.

The spelling of 66419643 in words is "sixty-six million, four hundred nineteen thousand, six hundred forty-three".