21453304 has 8 divisors (see below), whose sum is σ = 40224960. Its totient is φ = 10726648.

The previous prime is 21453293. The next prime is 21453307. The reversal of 21453304 is 40335412.

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21453307) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1340824 + ... + 1340839.

It is an arithmetic number, because the mean of its divisors is an integer number (5028120).

Almost surely, 2^21453304 is an apocalyptic number.

It is an amenable number.

21453304 is a deficient number, since it is larger than the sum of its proper divisors (18771656).

21453304 is a wasteful number, since it uses less digits than its factorization.

21453304 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2681669 (or 2681665 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 22.

The square root of 21453304 is about 4631.7711515143. The cubic root of 21453304 is about 277.8634320505.

Adding to 21453304 its reverse (40335412), we get a palindrome (61788716).

The spelling of 21453304 in words is "twenty-one million, four hundred fifty-three thousand, three hundred four".