21102320320 has 112 divisors (see below), whose sum is σ = 53381135808. Its totient is φ = 7918223360.

The previous prime is 21102320243. The next prime is 21102320359. The reversal of 21102320320 is 2302320112.

It is a Harshad number since it is a multiple of its sum of digits (16).

It is a junction number, because it is equal to n+sod(n) for n = 21102320294 and 21102320303.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1685604 + ... + 1698076.

It is an arithmetic number, because the mean of its divisors is an integer number (476617284).

Almost surely, 2^21102320320 is an apocalyptic number.

21102320320 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 21102320320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26690567904).

21102320320 is an abundant number, since it is smaller than the sum of its proper divisors (32278815488).

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

21102320320 is a wasteful number, since it uses less digits than its factorization.

21102320320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12818 (or 12808 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 16.

Adding to 21102320320 its reverse (2302320112), we get a palindrome (23404640432).

The spelling of 21102320320 in words is "twenty-one billion, one hundred two million, three hundred twenty thousand, three hundred twenty".