21323223180 has 432 divisors, whose sum is σ = 79010043840. Its totient is φ = 4632477696.

The previous prime is 21323223161. The next prime is 21323223193. The reversal of 21323223180 is 8132232312.

It is a happy number.

21323223180 is a `hidden beast` number, since 2 + 1 + 323 + 22 + 318 + 0 = 666.

It is an unprimeable number.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 52134816 + ... + 52135224.

It is an arithmetic number, because the mean of its divisors is an integer number (182893620).

Almost surely, 2^21323223180 is an apocalyptic number.

21323223180 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 21323223180, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39505021920).

21323223180 is an abundant number, since it is smaller than the sum of its proper divisors (57686820660).

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

21323223180 is a wasteful number, since it uses less digits than its factorization.

21323223180 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 718 (or 706 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 27.

Adding to 21323223180 its reverse (8132232312), we get a palindrome (29455455492).

The spelling of 21323223180 in words is "twenty-one billion, three hundred twenty-three million, two hundred twenty-three thousand, one hundred eighty".