21045066 has 32 divisors (see below), whose sum is σ = 48554880. Its totient is φ = 5956416.

The previous prime is 21045053. The next prime is 21045071. The reversal of 21045066 is 66054012.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 2280 + ... + 6876.

It is an arithmetic number, because the mean of its divisors is an integer number (1517340).

Almost surely, 2^21045066 is an apocalyptic number.

21045066 is an abundant number, since it is smaller than the sum of its proper divisors (27509814).

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

21045066 is a wasteful number, since it uses less digits than its factorization.

21045066 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4718.

The product of its (nonzero) digits is 1440, while the sum is 24.

The square root of 21045066 is about 4587.4901634772. The cubic root of 21045066 is about 276.0896316743.

Adding to 21045066 its reverse (66054012), we get a palindrome (87099078).

The spelling of 21045066 in words is "twenty-one million, forty-five thousand, sixty-six".