20641236 has 96 divisors (see below), whose sum is σ = 60963840. Its totient is φ = 5280000.

The previous prime is 20641223. The next prime is 20641253. The reversal of 20641236 is 63214602.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 82111 + ... + 82361.

It is an arithmetic number, because the mean of its divisors is an integer number (635040).

Almost surely, 2^20641236 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 20641236, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30481920).

20641236 is an abundant number, since it is smaller than the sum of its proper divisors (40322604).

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

20641236 is a wasteful number, since it uses less digits than its factorization.

20641236 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 365 (or 363 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 24.

The square root of 20641236 is about 4543.2627042688. The cubic root of 20641236 is about 274.3122694094.

Adding to 20641236 its reverse (63214602), we get a palindrome (83855838).

The spelling of 20641236 in words is "twenty million, six hundred forty-one thousand, two hundred thirty-six".