21052266 has 16 divisors (see below), whose sum is σ = 44320800. Its totient is φ = 6648048.

The previous prime is 21052261. The next prime is 21052267. The reversal of 21052266 is 66225012.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21052261) 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, 92221 + ... + 92448.

It is an arithmetic number, because the mean of its divisors is an integer number (2770050).

Almost surely, 2^21052266 is an apocalyptic number.

21052266 is an abundant number, since it is smaller than the sum of its proper divisors (23268534).

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

21052266 is a wasteful number, since it uses less digits than its factorization.

21052266 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 184693.

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

The square root of 21052266 is about 4588.2748391961. The cubic root of 21052266 is about 276.1211136171.

Adding to 21052266 its reverse (66225012), we get a palindrome (87277278).

It can be divided in two parts, 2105 and 2266, that added together give a triangular number (4371 = T₉₃).

The spelling of 21052266 in words is "twenty-one million, fifty-two thousand, two hundred sixty-six".