21063804 has 24 divisors (see below), whose sum is σ = 50478288. Its totient is φ = 6831360.

The previous prime is 21063803. The next prime is 21063817. The reversal of 21063804 is 40836012.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21063803) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 23277 + ... + 24164.

It is an arithmetic number, because the mean of its divisors is an integer number (2103262).

Almost surely, 2^21063804 is an apocalyptic number.

It is an amenable number.

21063804 is an abundant number, since it is smaller than the sum of its proper divisors (29414484).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21063804 is a wasteful number, since it uses less digits than its factorization.

21063804 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 47485 (or 47483 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 24.

The square root of 21063804 is about 4589.5320022852. The cubic root of 21063804 is about 276.1715484660.

Adding to 21063804 its reverse (40836012), we get a palindrome (61899816).

The spelling of 21063804 in words is "twenty-one million, sixty-three thousand, eight hundred four".