21013322220 has 288 divisors, whose sum is σ = 70725957120. Its totient is φ = 5049475200.

The previous prime is 21013322203. The next prime is 21013322233. The reversal of 21013322220 is 2222331012.

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

It is a junction number, because it is equal to n+sod(n) for n = 21013322193 and 21013322202.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 33301305 + ... + 33301935.

It is an arithmetic number, because the mean of its divisors is an integer number (245576240).

Almost surely, 2^21013322220 is an apocalyptic number.

21013322220 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 21013322220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35362978560).

21013322220 is an abundant number, since it is smaller than the sum of its proper divisors (49712634900).

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

21013322220 is a wasteful number, since it uses less digits than its factorization.

21013322220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 818 (or 791 counting only the distinct ones).

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

Adding to 21013322220 its reverse (2222331012), we get a palindrome (23235653232).

The spelling of 21013322220 in words is "twenty-one billion, thirteen million, three hundred twenty-two thousand, two hundred twenty".