21001100011320 has 512 divisors, whose sum is σ = 77257930014720. Its totient is φ = 4493944350720.

The previous prime is 21001100011289. The next prime is 21001100011337. The reversal of 21001100011320 is 2311000110012.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a junction number, because it is equal to n+sod(n) for n = 21001100011296 and 21001100011305.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 2219280909 + ... + 2219290371.

It is an arithmetic number, because the mean of its divisors is an integer number (150894394560).

Almost surely, 2^{21001100011320} is an apocalyptic number.

21001100011320 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 21001100011320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38628965007360).

21001100011320 is an abundant number, since it is smaller than the sum of its proper divisors (56256830003400).

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

21001100011320 is a wasteful number, since it uses less digits than its factorization.

21001100011320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15147 (or 15143 counting only the distinct ones).

The product of its (nonzero) digits is 12, while the sum is 12.

Adding to 21001100011320 its reverse (2311000110012), we get a palindrome (23312100121332).

The spelling of 21001100011320 in words is "twenty-one trillion, one billion, one hundred million, eleven thousand, three hundred twenty".