21224613 has 8 divisors (see below), whose sum is σ = 28320768. Its totient is φ = 14139104.

The previous prime is 21224591. The next prime is 21224617. The reversal of 21224613 is 31642212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21224613 - 2²¹ = 19127461 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21224613.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21224617) by changing a digit.

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, 6556 + ... + 9242.

It is an arithmetic number, because the mean of its divisors is an integer number (3540096).

Almost surely, 2^21224613 is an apocalyptic number.

It is an amenable number.

21224613 is a deficient number, since it is larger than the sum of its proper divisors (7096155).

21224613 is a wasteful number, since it uses less digits than its factorization.

21224613 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5323.

The product of its digits is 576, while the sum is 21.

The square root of 21224613 is about 4607.0177989671. The cubic root of 21224613 is about 276.8725666838.

Adding to 21224613 its reverse (31642212), we get a palindrome (52866825).

The spelling of 21224613 in words is "twenty-one million, two hundred twenty-four thousand, six hundred thirteen".