21334566 has 16 divisors (see below), whose sum is σ = 46548288. Its totient is φ = 6465000.

The previous prime is 21334561. The next prime is 21334613. The reversal of 21334566 is 66543312.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21334561) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 161560 + ... + 161691.

It is an arithmetic number, because the mean of its divisors is an integer number (2909268).

Almost surely, 2^21334566 is an apocalyptic number.

21334566 is an abundant number, since it is smaller than the sum of its proper divisors (25213722).

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

21334566 is a wasteful number, since it uses less digits than its factorization.

21334566 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 323267.

The product of its digits is 12960, while the sum is 30.

The square root of 21334566 is about 4618.9355916704. The cubic root of 21334566 is about 277.3498514082.

Adding to 21334566 its reverse (66543312), we get a palindrome (87877878).

The spelling of 21334566 in words is "twenty-one million, three hundred thirty-four thousand, five hundred sixty-six".