21347224 has 32 divisors (see below), whose sum is σ = 42134400. Its totient is φ = 10126080.

The previous prime is 21347213. The next prime is 21347233. The reversal of 21347224 is 42274312.

It is a happy number.

It is a congruent number.

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, 11257 + ... + 13015.

It is an arithmetic number, because the mean of its divisors is an integer number (1316700).

Almost surely, 2^21347224 is an apocalyptic number.

It is an amenable number.

21347224 is a deficient number, since it is larger than the sum of its proper divisors (20787176).

21347224 is a wasteful number, since it uses less digits than its factorization.

21347224 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1843 (or 1839 counting only the distinct ones).

The product of its digits is 2688, while the sum is 25.

The square root of 21347224 is about 4620.3056175972. The cubic root of 21347224 is about 277.4046919947.

The spelling of 21347224 in words is "twenty-one million, three hundred forty-seven thousand, two hundred twenty-four".