21320204 has 48 divisors (see below), whose sum is σ = 41126400. Its totient is φ = 9637056.

The previous prime is 21320203. The next prime is 21320209. The reversal of 21320204 is 40202312.

It is not an unprimeable number, because it can be changed into a prime (21320203) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 269837 + ... + 269915.

It is an arithmetic number, because the mean of its divisors is an integer number (856800).

Almost surely, 2^21320204 is an apocalyptic number.

It is an amenable number.

21320204 is a deficient number, since it is larger than the sum of its proper divisors (19806196).

21320204 is a wasteful number, since it uses less digits than its factorization.

21320204 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 222 (or 220 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 14.

The square root of 21320204 is about 4617.3806427454. The cubic root of 21320204 is about 277.2876019937.

Adding to 21320204 its reverse (40202312), we get a palindrome (61522516).

The spelling of 21320204 in words is "twenty-one million, three hundred twenty thousand, two hundred four".