21330223 has 12 divisors (see below), whose sum is σ = 23651280. Its totient is φ = 19196672.

The previous prime is 21330163. The next prime is 21330251. The reversal of 21330223 is 32203312.

It is not a de Polignac number, because 21330223 - 2¹³ = 21322031 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21330197 and 21330206.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21330823) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5043 + ... + 8251.

It is an arithmetic number, because the mean of its divisors is an integer number (1970940).

Almost surely, 2^21330223 is an apocalyptic number.

21330223 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

21330223 is a deficient number, since it is larger than the sum of its proper divisors (2321057).

21330223 is a wasteful number, since it uses less digits than its factorization.

21330223 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3266 (or 3249 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 16.

The square root of 21330223 is about 4618.4654377834. The cubic root of 21330223 is about 277.3310304309.

Adding to 21330223 its reverse (32203312), we get a palindrome (53533535).

The spelling of 21330223 in words is "twenty-one million, three hundred thirty thousand, two hundred twenty-three".