21364534320 has 320 divisors, whose sum is σ = 70521200640. Its totient is φ = 5341593600.

The previous prime is 21364534277. The next prime is 21364534379. The reversal of 21364534320 is 2343546312.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 78835785 + ... + 78836055.

It is an arithmetic number, because the mean of its divisors is an integer number (220378752).

Almost surely, 2^21364534320 is an apocalyptic number.

21364534320 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 21364534320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35260600320).

21364534320 is an abundant number, since it is smaller than the sum of its proper divisors (49156666320).

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

21364534320 is a wasteful number, since it uses less digits than its factorization.

21364534320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 604 (or 598 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 33.

The spelling of 21364534320 in words is "twenty-one billion, three hundred sixty-four million, five hundred thirty-four thousand, three hundred twenty".