21223030320 has 400 divisors, whose sum is σ = 75473240832. Its totient is φ = 5525936640.

The previous prime is 21223030303. The next prime is 21223030321. The reversal of 21223030320 is 2303032212.

It is a happy number.

21223030320 is a `hidden beast` number, since 21 + 22 + 303 + 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 = 21223030293 and 21223030302.

It is not an unprimeable number, because it can be changed into a prime (21223030321) by changing a digit.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 74992899 + ... + 74993181.

Almost surely, 2^21223030320 is an apocalyptic number.

21223030320 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 21223030320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37736620416).

21223030320 is an abundant number, since it is smaller than the sum of its proper divisors (54250210512).

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

21223030320 is a wasteful number, since it uses less digits than its factorization.

21223030320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 542 (or 527 counting only the distinct ones).

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

Adding to 21223030320 its reverse (2303032212), we get a palindrome (23526062532).

The spelling of 21223030320 in words is "twenty-one billion, two hundred twenty-three million, thirty thousand, three hundred twenty".