21329804 has 12 divisors (see below), whose sum is σ = 37600584. Its totient is φ = 10586784.

The previous prime is 21329801. The next prime is 21329821. The reversal of 21329804 is 40892312.

It is a plaindrome in base 16.

It is not an unprimeable number, because it can be changed into a prime (21329801) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 18914 + ... + 20009.

It is an arithmetic number, because the mean of its divisors is an integer number (3133382).

Almost surely, 2^21329804 is an apocalyptic number.

It is an amenable number.

21329804 is a deficient number, since it is larger than the sum of its proper divisors (16270780).

21329804 is a wasteful number, since it uses less digits than its factorization.

21329804 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39064 (or 39062 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 29.

The square root of 21329804 is about 4618.4200761732. The cubic root of 21329804 is about 277.3292145026.

The spelling of 21329804 in words is "twenty-one million, three hundred twenty-nine thousand, eight hundred four".