21304303220 has 12 divisors (see below), whose sum is σ = 44739036804. Its totient is φ = 8521721280.

The previous prime is 21304303211. The next prime is 21304303247. The reversal of 21304303220 is 2230340312.

It can be written as a sum of positive squares in 2 ways, for example, as 4054632976 + 17249670244 = 63676^2 + 131338^2 .

It is a Harshad number since it is a multiple of its sum of digits (20), and also a Moran number because the ratio is a prime number: 1065215161 = 21304303220 / (2 + 1 + 3 + 0 + 4 + 3 + 0 + 3 + 2 + 2 + 0).

It is a junction number, because it is equal to n+sod(n) for n = 21304303192 and 21304303201.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 532607561 + ... + 532607600.

It is an arithmetic number, because the mean of its divisors is an integer number (3728253067).

Almost surely, 2^21304303220 is an apocalyptic number.

21304303220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21304303220 is an abundant number, since it is smaller than the sum of its proper divisors (23434733584).

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

21304303220 is a wasteful number, since it uses less digits than its factorization.

21304303220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1065215170 (or 1065215168 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 20.

Adding to 21304303220 its reverse (2230340312), we get a palindrome (23534643532).

The spelling of 21304303220 in words is "twenty-one billion, three hundred four million, three hundred three thousand, two hundred twenty".