21080217600 has 1440 divisors, whose sum is σ = 92899366560. Its totient is φ = 4671406080.

The previous prime is 21080217593. The next prime is 21080217611. The reversal of 21080217600 is 671208012.

It is a tau number, because it is divible by the number of its divisors (1440).

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 119 ways as a sum of consecutive naturals, for example, 916531189 + ... + 916531211.

It is an arithmetic number, because the mean of its divisors is an integer number (64513449).

Almost surely, 2^21080217600 is an apocalyptic number.

21080217600 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 21080217600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (46449683280).

21080217600 is an abundant number, since it is smaller than the sum of its proper divisors (71819148960).

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

21080217600 is a wasteful number, since it uses less digits than its factorization.

21080217600 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 97 (or 63 counting only the distinct ones).

The product of its (nonzero) digits is 1344, while the sum is 27.

The spelling of 21080217600 in words is "twenty-one billion, eighty million, two hundred seventeen thousand, six hundred".