20428223 has 2 divisors, whose sum is σ = 20428224. Its totient is φ = 20428222.

The previous prime is 20428217. The next prime is 20428231. The reversal of 20428223 is 32282402.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20428223 - 2¹⁶ = 20362687 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20428273) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10214111 + 10214112.

It is an arithmetic number, because the mean of its divisors is an integer number (10214112).

Almost surely, 2^20428223 is an apocalyptic number.

20428223 is a deficient number, since it is larger than the sum of its proper divisors (1).

20428223 is an equidigital number, since it uses as much as digits as its factorization.

20428223 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1536, while the sum is 23.

The square root of 20428223 is about 4519.7591750004. The cubic root of 20428223 is about 273.3653906812.

The spelling of 20428223 in words is "twenty million, four hundred twenty-eight thousand, two hundred twenty-three".