21607781108928 has 672 divisors, whose sum is σ = 74313586460160. Its totient is φ = 5490507939840.

The previous prime is 21607781108897. The next prime is 21607781108939. The reversal of 21607781108928 is 82980118770612.

It is a tau number, because it is divible by the number of its divisors (672).

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 1206388293 + ... + 1206406203.

Almost surely, 2^{21607781108928} is an apocalyptic number.

21607781108928 is a gapful number since it is divisible by the number (28) 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 21607781108928, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37156793230080).

21607781108928 is an abundant number, since it is smaller than the sum of its proper divisors (52705805351232).

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

21607781108928 is a wasteful number, since it uses less digits than its factorization.

21607781108928 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18373 (or 18356 counting only the distinct ones).

The product of its (nonzero) digits is 5419008, while the sum is 60.

The spelling of 21607781108928 in words is "twenty-one trillion, six hundred seven billion, seven hundred eighty-one million, one hundred eight thousand, nine hundred twenty-eight".