20636224 has 56 divisors (see below), whose sum is σ = 47516288. Its totient is φ = 8709120.

The previous prime is 20636191. The next prime is 20636227. The reversal of 20636224 is 42263602.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (56).

It is not an unprimeable number, because it can be changed into a prime (20636227) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 32389 + ... + 33019.

Almost surely, 2^20636224 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20636224, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23758144).

20636224 is an abundant number, since it is smaller than the sum of its proper divisors (26880064).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20636224 is an equidigital number, since it uses as much as digits as its factorization.

20636224 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 723 (or 713 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 25.

The square root of 20636224 is about 4542.7110848039. The cubic root of 20636224 is about 274.2900652418.

Adding to 20636224 its reverse (42263602), we get a palindrome (62899826).

The spelling of 20636224 in words is "twenty million, six hundred thirty-six thousand, two hundred twenty-four".