21232223220 has 192 divisors, whose sum is σ = 67340206080. Its totient is φ = 4959263232.

The previous prime is 21232223191. The next prime is 21232223261. The reversal of 21232223220 is 2232223212.

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, 2273721 + ... + 2283039.

It is an arithmetic number, because the mean of its divisors is an integer number (350730240).

Almost surely, 2^21232223220 is an apocalyptic number.

21232223220 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 21232223220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33670103040).

21232223220 is an abundant number, since it is smaller than the sum of its proper divisors (46107982860).

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

21232223220 is a wasteful number, since it uses less digits than its factorization.

21232223220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9494 (or 9492 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 21.

Adding to 21232223220 its reverse (2232223212), we get a palindrome (23464446432).

The spelling of 21232223220 in words is "twenty-one billion, two hundred thirty-two million, two hundred twenty-three thousand, two hundred twenty".