21254648 has 8 divisors (see below), whose sum is σ = 39852480. Its totient is φ = 10627320.

The previous prime is 21254647. The next prime is 21254677. The reversal of 21254648 is 84645212.

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21254647) 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 as a sum of consecutive naturals, namely, 1328408 + ... + 1328423.

It is an arithmetic number, because the mean of its divisors is an integer number (4981560).

Almost surely, 2^21254648 is an apocalyptic number.

It is an amenable number.

21254648 is a deficient number, since it is larger than the sum of its proper divisors (18597832).

21254648 is a wasteful number, since it uses less digits than its factorization.

21254648 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2656837 (or 2656833 counting only the distinct ones).

The product of its digits is 15360, while the sum is 32.

The square root of 21254648 is about 4610.2763474655. The cubic root of 21254648 is about 277.0031061354.

The spelling of 21254648 in words is "twenty-one million, two hundred fifty-four thousand, six hundred forty-eight".