21513211300 has 144 divisors (see below), whose sum is σ = 55416453120. Its totient is φ = 7096026240.

The previous prime is 21513211273. The next prime is 21513211303. The reversal of 21513211300 is 311231512.

It is not an unprimeable number, because it can be changed into a prime (21513211303) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1935559 + ... + 1946641.

It is an arithmetic number, because the mean of its divisors is an integer number (384836480).

Almost surely, 2^21513211300 is an apocalyptic number.

21513211300 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 21513211300, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27708226560).

21513211300 is an abundant number, since it is smaller than the sum of its proper divisors (33903241820).

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

21513211300 is a wasteful number, since it uses less digits than its factorization.

21513211300 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11210 (or 11203 counting only the distinct ones).

The product of its (nonzero) digits is 180, while the sum is 19.

Adding to 21513211300 its reverse (311231512), we get a palindrome (21824442812).

The spelling of 21513211300 in words is "twenty-one billion, five hundred thirteen million, two hundred eleven thousand, three hundred".