21324494880 has 288 divisors, whose sum is σ = 79849866096. Its totient is φ = 5149827072.

The previous prime is 21324494837. The next prime is 21324494887. The reversal of 21324494880 is 8849442312.

It can be written as a sum of positive squares in 8 ways, for example, as 3096254736 + 18228240144 = 55644^2 + 135012^2 .

It is a tau number, because it is divible by the number of its divisors (288).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (21324494887) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 981414 + ... + 1002906.

Almost surely, 2^21324494880 is an apocalyptic number.

21324494880 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 21324494880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39924933048).

21324494880 is an abundant number, since it is smaller than the sum of its proper divisors (58525371216).

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

21324494880 is a wasteful number, since it uses less digits than its factorization.

21324494880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21580 (or 21569 counting only the distinct ones).

The product of its (nonzero) digits is 442368, while the sum is 45.

The spelling of 21324494880 in words is "twenty-one billion, three hundred twenty-four million, four hundred ninety-four thousand, eight hundred eighty".