21244324660 has 96 divisors (see below), whose sum is σ = 49290845184. Its totient is φ = 7641216000.

The previous prime is 21244324657. The next prime is 21244324679. The reversal of 21244324660 is 6642344212.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 10563055 + ... + 10565065.

It is an arithmetic number, because the mean of its divisors is an integer number (513446304).

Almost surely, 2^21244324660 is an apocalyptic number.

21244324660 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 21244324660, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24645422592).

21244324660 is an abundant number, since it is smaller than the sum of its proper divisors (28046520524).

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

21244324660 is a wasteful number, since it uses less digits than its factorization.

21244324660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3065 (or 3063 counting only the distinct ones).

The product of its (nonzero) digits is 55296, while the sum is 34.

Adding to 21244324660 its reverse (6642344212), we get a palindrome (27886668872).

The spelling of 21244324660 in words is "twenty-one billion, two hundred forty-four million, three hundred twenty-four thousand, six hundred sixty".