221424403 has 8 divisors (see below), whose sum is σ = 224841008. Its totient is φ = 218018304.

The previous prime is 221424377. The next prime is 221424431. The reversal of 221424403 is 304424122.

It is a happy number.

221424403 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221424403 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221424433) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 46876 + ... + 51382.

It is an arithmetic number, because the mean of its divisors is an integer number (28105126).

Almost surely, 2^221424403 is an apocalyptic number.

221424403 is a deficient number, since it is larger than the sum of its proper divisors (3416605).

221424403 is an equidigital number, since it uses as much as digits as its factorization.

221424403 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5253.

The product of its (nonzero) digits is 1536, while the sum is 22.

The square root of 221424403 is about 14880.3361185156. The cubic root of 221424403 is about 604.9811282049.

Adding to 221424403 its reverse (304424122), we get a palindrome (525848525).

The spelling of 221424403 in words is "two hundred twenty-one million, four hundred twenty-four thousand, four hundred three".