21320064000 has 704 divisors, whose sum is σ = 81748992000. Its totient is φ = 5474304000.

The previous prime is 21320063977. The next prime is 21320064011. The reversal of 21320064000 is 46002312.

It is a happy number.

21320064000 is a `hidden beast` number, since 2 + 1 + 3 + 20 + 0 + 640 + 0 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent 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, 107135901 + ... + 107136099.

Almost surely, 2^21320064000 is an apocalyptic number.

21320064000 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 21320064000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40874496000).

21320064000 is an abundant number, since it is smaller than the sum of its proper divisors (60428928000).

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

21320064000 is a wasteful number, since it uses less digits than its factorization.

21320064000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 274 (or 240 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 18.

Adding to 21320064000 its reverse (46002312), we get a palindrome (21366066312).

The spelling of 21320064000 in words is "twenty-one billion, three hundred twenty million, sixty-four thousand".