21525448 has 16 divisors (see below), whose sum is σ = 46126080. Its totient is φ = 9225168.

The previous prime is 21525419. The next prime is 21525463. The reversal of 21525448 is 84452512.

It is a congruent number.

It is an unprimeable number.

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, 192136 + ... + 192247.

It is an arithmetic number, because the mean of its divisors is an integer number (2882880).

Almost surely, 2^21525448 is an apocalyptic number.

21525448 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

21525448 is an abundant number, since it is smaller than the sum of its proper divisors (24600632).

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

21525448 is a wasteful number, since it uses less digits than its factorization.

21525448 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 384396 (or 384392 counting only the distinct ones).

The product of its digits is 12800, while the sum is 31.

The square root of 21525448 is about 4639.5525646338. The cubic root of 21525448 is about 278.1745535238.

The spelling of 21525448 in words is "twenty-one million, five hundred twenty-five thousand, four hundred forty-eight".