66655223 has 4 divisors (see below), whose sum is σ = 67499040. Its totient is φ = 65811408.

The previous prime is 66655213. The next prime is 66655243. The reversal of 66655223 is 32255666.

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 66655223 - 2⁶ = 66655159 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66655213) 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, 421790 + ... + 421947.

It is an arithmetic number, because the mean of its divisors is an integer number (16874760).

Almost surely, 2^66655223 is an apocalyptic number.

66655223 is a deficient number, since it is larger than the sum of its proper divisors (843817).

66655223 is an equidigital number, since it uses as much as digits as its factorization.

66655223 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 843816.

The product of its digits is 64800, while the sum is 35.

The square root of 66655223 is about 8164.2650005986. The cubic root of 66655223 is about 405.4569308132.

The spelling of 66655223 in words is "sixty-six million, six hundred fifty-five thousand, two hundred twenty-three".