20668544 has 32 divisors (see below), whose sum is σ = 44346540. Its totient is φ = 9538560.

The previous prime is 20668541. The next prime is 20668553. The reversal of 20668544 is 44586602.

It can be written as a sum of positive squares in 2 ways, for example, as 20430400 + 238144 = 4520^2 + 488^2 .

It is a tau number, because it is divible by the number of its divisors (32).

It is a super-2 number, since 2×20668544² = 854377422159872, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (20668541) 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, 4547 + ... + 7874.

Almost surely, 2^20668544 is an apocalyptic number.

It is an amenable number.

20668544 is an abundant number, since it is smaller than the sum of its proper divisors (23677996).

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

20668544 is a wasteful number, since it uses less digits than its factorization.

20668544 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12448 (or 12436 counting only the distinct ones).

The product of its (nonzero) digits is 46080, while the sum is 35.

The square root of 20668544 is about 4546.2670401110. The cubic root of 20668544 is about 274.4331862386.

It can be divided in two parts, 20668 and 544, that added together give a palindrome (21212).

The spelling of 20668544 in words is "twenty million, six hundred sixty-eight thousand, five hundred forty-four".