21513415155200 has 120 divisors (see below), whose sum is σ = 53323553655240. Its totient is φ = 8601751756800.

The previous prime is 21513415155157. The next prime is 21513415155229. The reversal of 21513415155200 is 255151431512.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 30227435 + ... + 30930965.

It is an arithmetic number, because the mean of its divisors is an integer number (444362947127).

Almost surely, 2^{21513415155200} is an apocalyptic number.

21513415155200 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 21513415155200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26661776827620).

21513415155200 is an abundant number, since it is smaller than the sum of its proper divisors (31810138500040).

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

21513415155200 is an equidigital number, since it uses as much as digits as its factorization.

21513415155200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 705948 (or 705927 counting only the distinct ones).

The product of its (nonzero) digits is 30000, while the sum is 35.

Adding to 21513415155200 its reverse (255151431512), we get a palindrome (21768566586712).

The spelling of 21513415155200 in words is "twenty-one trillion, five hundred thirteen billion, four hundred fifteen million, one hundred fifty-five thousand, two hundred".