21524080 has 40 divisors (see below), whose sum is σ = 51215472. Its totient is φ = 8408064.

The previous prime is 21524059. The next prime is 21524089. The reversal of 21524080 is 8042512.

It is a tau number, because it is divible by the number of its divisors (40).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21524089) 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 7 ways as a sum of consecutive naturals, for example, 312 + ... + 6568.

Almost surely, 2^21524080 is an apocalyptic number.

21524080 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21524080, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25607736).

21524080 is an abundant number, since it is smaller than the sum of its proper divisors (29691392).

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

21524080 is a wasteful number, since it uses less digits than its factorization.

21524080 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6313 (or 6307 counting only the distinct ones).

The product of its (nonzero) digits is 640, while the sum is 22.

The square root of 21524080 is about 4639.4051342818. The cubic root of 21524080 is about 278.1686604857.

Adding to 21524080 its reverse (8042512), we get a palindrome (29566592).

The spelling of 21524080 in words is "twenty-one million, five hundred twenty-four thousand, eighty".