21214304 has 12 divisors (see below), whose sum is σ = 41765724. Its totient is φ = 10607136.

The previous prime is 21214273. The next prime is 21214309. The reversal of 21214304 is 40341212.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21214309) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 331442 + ... + 331505.

It is an arithmetic number, because the mean of its divisors is an integer number (3480477).

Almost surely, 2^21214304 is an apocalyptic number.

It is an amenable number.

21214304 is a deficient number, since it is larger than the sum of its proper divisors (20551420).

21214304 is an equidigital number, since it uses as much as digits as its factorization.

21214304 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 662957 (or 662949 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 17.

The square root of 21214304 is about 4605.8988265050. The cubic root of 21214304 is about 276.8277328623.

Adding to 21214304 its reverse (40341212), we get a palindrome (61555516).

The spelling of 21214304 in words is "twenty-one million, two hundred fourteen thousand, three hundred four".