21732066 has 24 divisors (see below), whose sum is σ = 47174400. Its totient is φ = 7230456.

The previous prime is 21732059. The next prime is 21732077. The reversal of 21732066 is 66023712.

It is a happy number.

It is a Curzon number.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 14835 + ... + 16233.

It is an arithmetic number, because the mean of its divisors is an integer number (1965600).

Almost surely, 2^21732066 is an apocalyptic number.

21732066 is an abundant number, since it is smaller than the sum of its proper divisors (25442334).

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

21732066 is a wasteful number, since it uses less digits than its factorization.

21732066 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2270 (or 2267 counting only the distinct ones).

The product of its (nonzero) digits is 3024, while the sum is 27.

The square root of 21732066 is about 4661.7664034141. The cubic root of 21732066 is about 279.0617661068.

Adding to 21732066 its reverse (66023712), we get a palindrome (87755778).

The spelling of 21732066 in words is "twenty-one million, seven hundred thirty-two thousand, sixty-six".