21052212 has 24 divisors (see below), whose sum is σ = 49288512. Its totient is φ = 6993600.

The previous prime is 21052177. The next prime is 21052217. The reversal of 21052212 is 21225012.

It is a junction number, because it is equal to n+sod(n) for n = 21052191 and 21052200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21052217) by changing a digit.

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, 912 + ... + 6552.

It is an arithmetic number, because the mean of its divisors is an integer number (2053688).

Almost surely, 2^21052212 is an apocalyptic number.

It is an amenable number.

21052212 is an abundant number, since it is smaller than the sum of its proper divisors (28236300).

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

21052212 is a wasteful number, since it uses less digits than its factorization.

21052212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5959 (or 5957 counting only the distinct ones).

The product of its (nonzero) digits is 80, while the sum is 15.

The square root of 21052212 is about 4588.2689546277. The cubic root of 21052212 is about 276.1208775293.

Adding to 21052212 its reverse (21225012), we get a palindrome (42277224).

The spelling of 21052212 in words is "twenty-one million, fifty-two thousand, two hundred twelve".