21270664800 has 1728 divisors, whose sum is σ = 102368448000. Its totient is φ = 4267468800.

The previous prime is 21270664777. The next prime is 21270664801. The reversal of 21270664800 is 846607212.

21270664800 is a `hidden beast` number, since 2 + 1 + 2 + 7 + 0 + 6 + 648 + 0 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21270664801) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 287 ways as a sum of consecutive naturals, for example, 733471186 + ... + 733471214.

It is an arithmetic number, because the mean of its divisors is an integer number (59241000).

Almost surely, 2^21270664800 is an apocalyptic number.

21270664800 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 21270664800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (51184224000).

21270664800 is an abundant number, since it is smaller than the sum of its proper divisors (81097783200).

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

21270664800 is a wasteful number, since it uses less digits than its factorization.

21270664800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 96 (or 57 counting only the distinct ones).

The product of its (nonzero) digits is 32256, while the sum is 36.

The spelling of 21270664800 in words is "twenty-one billion, two hundred seventy million, six hundred sixty-four thousand, eight hundred".