21304365 has 8 divisors (see below), whose sum is σ = 34087008. Its totient is φ = 11362320.

The previous prime is 21304351. The next prime is 21304373. The reversal of 21304365 is 56340312.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21304365 - 2⁵ = 21304333 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 710131 + ... + 710160.

It is an arithmetic number, because the mean of its divisors is an integer number (4260876).

Almost surely, 2^21304365 is an apocalyptic number.

It is an amenable number.

21304365 is a deficient number, since it is larger than the sum of its proper divisors (12782643).

21304365 is a wasteful number, since it uses less digits than its factorization.

21304365 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1420299.

The product of its (nonzero) digits is 2160, while the sum is 24.

The square root of 21304365 is about 4615.6651741650. The cubic root of 21304365 is about 277.2189183734.

Adding to 21304365 its reverse (56340312), we get a palindrome (77644677).

The spelling of 21304365 in words is "twenty-one million, three hundred four thousand, three hundred sixty-five".