21221444310 has 128 divisors (see below), whose sum is σ = 56419545600. Its totient is φ = 5065728000.

The previous prime is 21221444287. The next prime is 21221444311. The reversal of 21221444310 is 1344412212.

It is a super-2 number, since 2×21221444310² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21221444311) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 6431041 + ... + 6434339.

It is an arithmetic number, because the mean of its divisors is an integer number (440777700).

Almost surely, 2^21221444310 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21221444310, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28209772800).

21221444310 is an abundant number, since it is smaller than the sum of its proper divisors (35198101290).

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

21221444310 is a wasteful number, since it uses less digits than its factorization.

21221444310 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3614.

The product of its (nonzero) digits is 1536, while the sum is 24.

Adding to 21221444310 its reverse (1344412212), we get a palindrome (22565856522).

The spelling of 21221444310 in words is "twenty-one billion, two hundred twenty-one million, four hundred forty-four thousand, three hundred ten".