223666 has 4 divisors (see below), whose sum is σ = 335502. Its totient is φ = 111832.

The previous prime is 223637. The next prime is 223667. The reversal of 223666 is 666322.

223666 is digitally balanced in base 3, 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: 666322 = 2 ⋅333161.

It can be written as a sum of positive squares in only one way, i.e., 207025 + 16641 = 455^2 + 129^2 .

It is a plaindrome in base 10.

It is a self number, because there is not a number n which added to its sum of digits gives 223666.

It is not an unprimeable number, because it can be changed into a prime (223667) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 55915 + ... + 55918.

2²²³⁶⁶⁶ is an apocalyptic number.

223666 is a deficient number, since it is larger than the sum of its proper divisors (111836).

223666 is a wasteful number, since it uses less digits than its factorization.

223666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 111835.

The product of its digits is 2592, while the sum is 25.

The square root of 223666 is about 472.9333991166. The cubic root of 223666 is about 60.7015792820.

Adding to 223666 its reverse (666322), we get a palindrome (889988).

The spelling of 223666 in words is "two hundred twenty-three thousand, six hundred sixty-six".