21333245 has 8 divisors (see below), whose sum is σ = 25698816. Its totient is φ = 17000656.

The previous prime is 21333199. The next prime is 21333251. The reversal of 21333245 is 54233312.

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 21333245 - 2¹⁰ = 21332221 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21333245.

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, 6797 + ... + 9426.

It is an arithmetic number, because the mean of its divisors is an integer number (3212352).

Almost surely, 2^21333245 is an apocalyptic number.

It is an amenable number.

21333245 is a deficient number, since it is larger than the sum of its proper divisors (4365571).

21333245 is a wasteful number, since it uses less digits than its factorization.

21333245 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16491.

The product of its digits is 2160, while the sum is 23.

The square root of 21333245 is about 4618.7925911433. The cubic root of 21333245 is about 277.3441269465.

Adding to 21333245 its reverse (54233312), we get a palindrome (75566557).

The spelling of 21333245 in words is "twenty-one million, three hundred thirty-three thousand, two hundred forty-five".