21684065000 has 160 divisors (see below), whose sum is σ = 54960407040. Its totient is φ = 7970400000.

The previous prime is 21684064999. The next prime is 21684065021. The reversal of 21684065000 is 56048612.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 17614385 + ... + 17615615.

It is an arithmetic number, because the mean of its divisors is an integer number (343502544).

Almost surely, 2^21684065000 is an apocalyptic number.

21684065000 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 21684065000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27480203520).

21684065000 is an abundant number, since it is smaller than the sum of its proper divisors (33276342040).

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

21684065000 is a wasteful number, since it uses less digits than its factorization.

21684065000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1541 (or 1522 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 32.

The spelling of 21684065000 in words is "twenty-one billion, six hundred eighty-four million, sixty-five thousand".