21708766080 has 768 divisors, whose sum is σ = 83518905600. Its totient is φ = 5173149696.

The previous prime is 21708766067. The next prime is 21708766091. The reversal of 21708766080 is 8066780712.

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

It is a congruent number.

It is an unprimeable number.

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 95 ways as a sum of consecutive naturals, for example, 243918676 + ... + 243918764.

It is an arithmetic number, because the mean of its divisors is an integer number (108748575).

Almost surely, 2^21708766080 is an apocalyptic number.

21708766080 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 21708766080, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41759452800).

21708766080 is an abundant number, since it is smaller than the sum of its proper divisors (61810139520).

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

21708766080 is a wasteful number, since it uses less digits than its factorization.

21708766080 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 231 (or 216 counting only the distinct ones).

The product of its (nonzero) digits is 225792, while the sum is 45.

The spelling of 21708766080 in words is "twenty-one billion, seven hundred eight million, seven hundred sixty-six thousand, eighty".