21033220320 has 384 divisors, whose sum is σ = 87793735680. Its totient is φ = 4598415360.

The previous prime is 21033220279. The next prime is 21033220333. The reversal of 21033220320 is 2302233012.

It is a happy number.

21033220320 is a `hidden beast` number, since 2 + 10 + 332 + 2 + 0 + 320 = 666.

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 = 21033220293 and 21033220302.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 680400 + ... + 710640.

It is an arithmetic number, because the mean of its divisors is an integer number (228629520).

Almost surely, 2^21033220320 is an apocalyptic number.

21033220320 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 21033220320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (43896867840).

21033220320 is an abundant number, since it is smaller than the sum of its proper divisors (66760515360).

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

21033220320 is a wasteful number, since it uses less digits than its factorization.

21033220320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30295 (or 30281 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 18.

Adding to 21033220320 its reverse (2302233012), we get a palindrome (23335453332).

The spelling of 21033220320 in words is "twenty-one billion, thirty-three million, two hundred twenty thousand, three hundred twenty".