21504248 has 16 divisors (see below), whose sum is σ = 40545960. Its totient is φ = 10692000.

The previous prime is 21504247. The next prime is 21504251. The reversal of 21504248 is 84240512.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21504247) 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, 5978 + ... + 8873.

Almost surely, 2^21504248 is an apocalyptic number.

It is an amenable number.

21504248 is a deficient number, since it is larger than the sum of its proper divisors (19041712).

21504248 is a wasteful number, since it uses less digits than its factorization.

21504248 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15038 (or 15034 counting only the distinct ones).

The product of its (nonzero) digits is 2560, while the sum is 26.

The square root of 21504248 is about 4637.2672987439. The cubic root of 21504248 is about 278.0832006029.

The spelling of 21504248 in words is "twenty-one million, five hundred four thousand, two hundred forty-eight".