21680406000 has 1280 divisors, whose sum is σ = 95265331200. Its totient is φ = 4644864000.

The previous prime is 21680405987. The next prime is 21680406023. The reversal of 21680406000 is 60408612.

21680406000 is a `hidden beast` number, since 2 + 16 + 8 + 0 + 40 + 600 + 0 = 666.

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 polite number, since it can be written in 255 ways as a sum of consecutive naturals, for example, 191861944 + ... + 191862056.

It is an arithmetic number, because the mean of its divisors is an integer number (74426040).

Almost surely, 2^21680406000 is an apocalyptic number.

21680406000 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 21680406000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (47632665600).

21680406000 is an abundant number, since it is smaller than the sum of its proper divisors (73584925200).

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

21680406000 is a wasteful number, since it uses less digits than its factorization.

21680406000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 192 (or 170 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 27.

The spelling of 21680406000 in words is "twenty-one billion, six hundred eighty million, four hundred six thousand".