21412524 has 24 divisors (see below), whose sum is σ = 57100288. Its totient is φ = 6117840.

The previous prime is 21412513. The next prime is 21412549. The reversal of 21412524 is 42521412.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a self number, because there is not a number n which added to its sum of digits gives 21412524.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 127372 + ... + 127539.

Almost surely, 2^21412524 is an apocalyptic number.

It is an amenable number.

21412524 is an abundant number, since it is smaller than the sum of its proper divisors (35687764).

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

21412524 is a wasteful number, since it uses less digits than its factorization.

21412524 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 254925 (or 254923 counting only the distinct ones).

The product of its digits is 640, while the sum is 21.

The square root of 21412524 is about 4627.3668538382. The cubic root of 21412524 is about 277.6872593715.

Adding to 21412524 its reverse (42521412), we get a palindrome (63933936).

The spelling of 21412524 in words is "twenty-one million, four hundred twelve thousand, five hundred twenty-four".