20668223 has 4 divisors (see below), whose sum is σ = 21172368. Its totient is φ = 20164080.

The previous prime is 20668211. The next prime is 20668229. The reversal of 20668223 is 32286602.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 32286602 = 2 ⋅16143301.

It is a cyclic number.

It is not a de Polignac number, because 20668223 - 2⁸ = 20667967 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 (20668229) 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, 252011 + ... + 252092.

It is an arithmetic number, because the mean of its divisors is an integer number (5293092).

Almost surely, 2^20668223 is an apocalyptic number.

20668223 is a deficient number, since it is larger than the sum of its proper divisors (504145).

20668223 is an equidigital number, since it uses as much as digits as its factorization.

20668223 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 504144.

The product of its (nonzero) digits is 6912, while the sum is 29.

The square root of 20668223 is about 4546.2317362845. The cubic root of 20668223 is about 274.4317655046.

The spelling of 20668223 in words is "twenty million, six hundred sixty-eight thousand, two hundred twenty-three".