21527224 has 16 divisors (see below), whose sum is σ = 40419000. Its totient is φ = 10748832.

The previous prime is 21527213. The next prime is 21527227. The reversal of 21527224 is 42272512.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21527227) 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, 6627 + ... + 9325.

Almost surely, 2^21527224 is an apocalyptic number.

It is an amenable number.

21527224 is a deficient number, since it is larger than the sum of its proper divisors (18891776).

21527224 is a wasteful number, since it uses less digits than its factorization.

21527224 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3702 (or 3698 counting only the distinct ones).

The product of its digits is 2240, while the sum is 25.

The square root of 21527224 is about 4639.7439584529. The cubic root of 21527224 is about 278.1822037621.

Adding to 21527224 its reverse (42272512), we get a palindrome (63799736).

It can be divided in two parts, 215272 and 24, that added together give a square (215296 = 464²).

The spelling of 21527224 in words is "twenty-one million, five hundred twenty-seven thousand, two hundred twenty-four".