21203323020 has 240 divisors, whose sum is σ = 74334861216. Its totient is φ = 5014656000.

The previous prime is 21203323013. The next prime is 21203323021. The reversal of 21203323020 is 2032330212.

It is a happy number.

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 = 21203322984 and 21203323002.

It is not an unprimeable number, because it can be changed into a prime (21203323021) 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, 716110 + ... + 745130.

Almost surely, 2^21203323020 is an apocalyptic number.

21203323020 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 21203323020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37167430608).

21203323020 is an abundant number, since it is smaller than the sum of its proper divisors (53131538196).

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

21203323020 is a wasteful number, since it uses less digits than its factorization.

21203323020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29094 (or 29083 counting only the distinct ones).

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

Adding to 21203323020 its reverse (2032330212), we get a palindrome (23235653232).

The spelling of 21203323020 in words is "twenty-one billion, two hundred three million, three hundred twenty-three thousand, twenty".