21300012220 has 96 divisors (see below), whose sum is σ = 46947600000. Its totient is φ = 8106835968.

The previous prime is 21300012127. The next prime is 21300012229. The reversal of 21300012220 is 2221000312.

It is a self number, because there is not a number n which added to its sum of digits gives 21300012220.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21300012229) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 23176921 + ... + 23177839.

It is an arithmetic number, because the mean of its divisors is an integer number (489037500).

Almost surely, 2^21300012220 is an apocalyptic number.

21300012220 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 21300012220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23473800000).

21300012220 is an abundant number, since it is smaller than the sum of its proper divisors (25647587780).

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

21300012220 is a wasteful number, since it uses less digits than its factorization.

21300012220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1495 (or 1493 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 13.

Adding to 21300012220 its reverse (2221000312), we get a palindrome (23521012532).

The spelling of 21300012220 in words is "twenty-one billion, three hundred million, twelve thousand, two hundred twenty".