66728183 has 4 divisors (see below), whose sum is σ = 66939000. Its totient is φ = 66517368.

The previous prime is 66728177. The next prime is 66728231. The reversal of 66728183 is 38182766.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 66728183 - 2¹⁶ = 66662647 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 66728183.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66728153) 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 3 ways as a sum of consecutive naturals, for example, 104933 + ... + 105566.

It is an arithmetic number, because the mean of its divisors is an integer number (16734750).

Almost surely, 2^66728183 is an apocalyptic number.

66728183 is a deficient number, since it is larger than the sum of its proper divisors (210817).

66728183 is a wasteful number, since it uses less digits than its factorization.

66728183 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 210816.

The product of its digits is 96768, while the sum is 41.

The square root of 66728183 is about 8168.7320313498. The cubic root of 66728183 is about 405.6048129520.

The spelling of 66728183 in words is "sixty-six million, seven hundred twenty-eight thousand, one hundred eighty-three".