21544648 has 16 divisors (see below), whose sum is σ = 40472460. Its totient is φ = 10752000.

The previous prime is 21544631. The next prime is 21544669. The reversal of 21544648 is 84644512.

It can be written as a sum of positive squares in 2 ways, for example, as 19166884 + 2377764 = 4378^2 + 1542^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2568 + ... + 7048.

Almost surely, 2^21544648 is an apocalyptic number.

It is an amenable number.

21544648 is a deficient number, since it is larger than the sum of its proper divisors (18927812).

21544648 is a wasteful number, since it uses less digits than its factorization.

21544648 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5088 (or 5084 counting only the distinct ones).

The product of its digits is 30720, while the sum is 34.

The square root of 21544648 is about 4641.6212684794. The cubic root of 21544648 is about 278.2572364986.

The spelling of 21544648 in words is "twenty-one million, five hundred forty-four thousand, six hundred forty-eight".