21652266 has 16 divisors (see below), whose sum is σ = 43426944. Its totient is φ = 7197024.

The previous prime is 21652219. The next prime is 21652273. The reversal of 21652266 is 66225612.

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 7 ways as a sum of consecutive naturals, for example, 2715 + ... + 7118.

It is an arithmetic number, because the mean of its divisors is an integer number (2714184).

Almost surely, 2^21652266 is an apocalyptic number.

21652266 is an abundant number, since it is smaller than the sum of its proper divisors (21774678).

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

21652266 is a wasteful number, since it uses less digits than its factorization.

21652266 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10205.

The product of its digits is 8640, while the sum is 30.

The square root of 21652266 is about 4653.1995443995. The cubic root of 21652266 is about 278.7197761945.

Adding to 21652266 its reverse (66225612), we get a palindrome (87877878).

The spelling of 21652266 in words is "twenty-one million, six hundred fifty-two thousand, two hundred sixty-six".