21701113728 has 384 divisors, whose sum is σ = 69924280320. Its totient is φ = 5941039104.

The previous prime is 21701113723. The next prime is 21701113741. The reversal of 21701113728 is 82731110712.

It is a tau number, because it is divible by the number of its divisors (384).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21701113723) by changing a digit.

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 47 ways as a sum of consecutive naturals, for example, 46870425 + ... + 46870887.

It is an arithmetic number, because the mean of its divisors is an integer number (182094480).

Almost surely, 2^21701113728 is an apocalyptic number.

21701113728 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 21701113728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34962140160).

21701113728 is an abundant number, since it is smaller than the sum of its proper divisors (48223166592).

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

21701113728 is a wasteful number, since it uses less digits than its factorization.

21701113728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 594 (or 575 counting only the distinct ones).

The product of its (nonzero) digits is 4704, while the sum is 33.

The spelling of 21701113728 in words is "twenty-one billion, seven hundred one million, one hundred thirteen thousand, seven hundred twenty-eight".