21224011 has 8 divisors (see below), whose sum is σ = 21657600. Its totient is φ = 20793000.

The previous prime is 21224003. The next prime is 21224023. The reversal of 21224011 is 11042212.

It is a happy number.

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 21224011 - 2³ = 21224003 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21223982 and 21224000.

It is not an unprimeable number, because it can be changed into a prime (21224081) 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, 27886 + ... + 28636.

It is an arithmetic number, because the mean of its divisors is an integer number (2707200).

Almost surely, 2^21224011 is an apocalyptic number.

21224011 is a deficient number, since it is larger than the sum of its proper divisors (433589).

21224011 is an equidigital number, since it uses as much as digits as its factorization.

21224011 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1289.

The product of its (nonzero) digits is 32, while the sum is 13.

The square root of 21224011 is about 4606.9524633970. The cubic root of 21224011 is about 276.8699489862.

Adding to 21224011 its reverse (11042212), we get a palindrome (32266223).

The spelling of 21224011 in words is "twenty-one million, two hundred twenty-four thousand, eleven".