21300000000 has 324 divisors, whose sum is σ = 71859338208. Its totient is φ = 5600000000.

The previous prime is 21299999971. The next prime is 21300000017. The reversal of 21300000000 is 312.

It is a Harshad number since it is a multiple of its sum of digits (6).

It is a super Niven number, because it is divisible the sum of any subset of its (nonzero) digits.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 299999965 + ... + 300000035.

Almost surely, 2^21300000000 is an apocalyptic number.

21300000000 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 21300000000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35929669104).

21300000000 is an abundant number, since it is smaller than the sum of its proper divisors (50559338208).

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

21300000000 is an frugal number, since it uses more digits than its factorization.

21300000000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 130 (or 81 counting only the distinct ones).

The product of its (nonzero) digits is 6, while the sum is 6.

Adding to 21300000000 its reverse (312), we get a palindrome (21300000312).

The spelling of 21300000000 in words is "twenty-one billion, three hundred million", and thus it is an aban number.