66128423 has 4 divisors (see below), whose sum is σ = 66229128. Its totient is φ = 66027720.

The previous prime is 66128411. The next prime is 66128441. The reversal of 66128423 is 32482166.

66128423 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 32482166 = 2 ⋅16241083.

It is a cyclic number.

It is not a de Polignac number, because 66128423 - 2²⁴ = 49351207 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 66128423.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66128443) 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 3 ways as a sum of consecutive naturals, for example, 49361 + ... + 50682.

It is an arithmetic number, because the mean of its divisors is an integer number (16557282).

Almost surely, 2^66128423 is an apocalyptic number.

66128423 is a deficient number, since it is larger than the sum of its proper divisors (100705).

66128423 is a wasteful number, since it uses less digits than its factorization.

66128423 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 100704.

The product of its digits is 13824, while the sum is 32.

The square root of 66128423 is about 8131.9384527922. The cubic root of 66128423 is about 404.3859474735.

The spelling of 66128423 in words is "sixty-six million, one hundred twenty-eight thousand, four hundred twenty-three".