21222102210 has 32 divisors (see below), whose sum is σ = 52309616832. Its totient is φ = 5506274880.

The previous prime is 21222102169. The next prime is 21222102211. The reversal of 21222102210 is 1220122212.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21222102210.

It is not an unprimeable number, because it can be changed into a prime (21222102211) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9558396 + ... + 9560615.

It is an arithmetic number, because the mean of its divisors is an integer number (1634675526).

Almost surely, 2^21222102210 is an apocalyptic number.

21222102210 is an abundant number, since it is smaller than the sum of its proper divisors (31087514622).

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

21222102210 is a wasteful number, since it uses less digits than its factorization.

21222102210 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19119058.

The product of its (nonzero) digits is 64, while the sum is 15.

Adding to 21222102210 its reverse (1220122212), we get a palindrome (22442224422).

The spelling of 21222102210 in words is "twenty-one billion, two hundred twenty-two million, one hundred two thousand, two hundred ten".