21222030312 has 192 divisors, whose sum is σ = 67258114560. Its totient is φ = 5920128000.

The previous prime is 21222030293. The next prime is 21222030317. The reversal of 21222030312 is 21303022212.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is not an unprimeable number, because it can be changed into a prime (21222030317) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 3713137 + ... + 3718847.

It is an arithmetic number, because the mean of its divisors is an integer number (350302680).

Almost surely, 2^21222030312 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 21222030312, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33629057280).

21222030312 is an abundant number, since it is smaller than the sum of its proper divisors (46036084248).

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

21222030312 is a wasteful number, since it uses less digits than its factorization.

21222030312 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5904 (or 5897 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 18.

Adding to 21222030312 its reverse (21303022212), we get a palindrome (42525052524).

The spelling of 21222030312 in words is "twenty-one billion, two hundred twenty-two million, thirty thousand, three hundred twelve".