21222000212 has 48 divisors (see below), whose sum is σ = 43852677120. Its totient is φ = 8793813600.

The previous prime is 21222000209. The next prime is 21222000251. The reversal of 21222000212 is 21200022212.

It is a Harshad number since it is a multiple of its sum of digits (14).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1005989 + ... + 1026867.

It is an arithmetic number, because the mean of its divisors is an integer number (913597440).

Almost surely, 2^21222000212 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21222000212, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21926338560).

21222000212 is an abundant number, since it is smaller than the sum of its proper divisors (22630676908).

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

21222000212 is a wasteful number, since it uses less digits than its factorization.

21222000212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22092 (or 22090 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 14.

Adding to 21222000212 its reverse (21200022212), we get a palindrome (42422022424).

It can be divided in two parts, 21222000 and 212, that added together give a palindrome (21222212).

The spelling of 21222000212 in words is "twenty-one billion, two hundred twenty-two million, two hundred twelve", and thus it is an aban number.