21544136 has 16 divisors (see below), whose sum is σ = 40446000. Its totient is φ = 10758544.

The previous prime is 21544109. The next prime is 21544139. The reversal of 21544136 is 63144512.

It is not an unprimeable number, because it can be changed into a prime (21544139) 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, 9215 + ... + 11313.

It is an arithmetic number, because the mean of its divisors is an integer number (2527875).

Almost surely, 2^21544136 is an apocalyptic number.

It is an amenable number.

21544136 is a deficient number, since it is larger than the sum of its proper divisors (18901864).

21544136 is a wasteful number, since it uses less digits than its factorization.

21544136 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3388 (or 3384 counting only the distinct ones).

The product of its digits is 2880, while the sum is 26.

The square root of 21544136 is about 4641.5661150090. The cubic root of 21544136 is about 278.2550322570.

Adding to 21544136 its reverse (63144512), we get a palindrome (84688648).

The spelling of 21544136 in words is "twenty-one million, five hundred forty-four thousand, one hundred thirty-six".