21220000320 has 224 divisors, whose sum is σ = 68316213888. Its totient is φ = 5580029952.

The previous prime is 21220000301. The next prime is 21220000331. The reversal of 21220000320 is 2300002212.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a junction number, because it is equal to n+sod(n) for n = 21220000296 and 21220000305.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 34616334 + ... + 34616946.

Almost surely, 2^21220000320 is an apocalyptic number.

21220000320 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21220000320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34158106944).

21220000320 is an abundant number, since it is smaller than the sum of its proper divisors (47096213568).

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

21220000320 is a wasteful number, since it uses less digits than its factorization.

21220000320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1077 (or 1067 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 12.

Adding to 21220000320 its reverse (2300002212), we get a palindrome (23520002532).

The spelling of 21220000320 in words is "twenty-one billion, two hundred twenty million, three hundred twenty", and thus it is an aban number.