20644312 has 16 divisors (see below), whose sum is σ = 41685840. Its totient is φ = 9528096.

The previous prime is 20644303. The next prime is 20644319. The reversal of 20644312 is 21344602.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20644319) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 99148 + ... + 99355.

It is an arithmetic number, because the mean of its divisors is an integer number (2605365).

Almost surely, 2^20644312 is an apocalyptic number.

It is an amenable number.

20644312 is an abundant number, since it is smaller than the sum of its proper divisors (21041528).

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

20644312 is a wasteful number, since it uses less digits than its factorization.

20644312 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 198522 (or 198518 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 22.

The square root of 20644312 is about 4543.6012148955. The cubic root of 20644312 is about 274.3258949279.

Adding to 20644312 its reverse (21344602), we get a palindrome (41988914).

The spelling of 20644312 in words is "twenty million, six hundred forty-four thousand, three hundred twelve".