21125758752 has 144 divisors (see below), whose sum is σ = 68720363712. Its totient is φ = 6030512640.

The previous prime is 21125758751. The next prime is 21125758793. The reversal of 21125758752 is 25785752112.

21125758752 is a `hidden beast` number, since 2 + 1 + 1 + 2 + 575 + 8 + 75 + 2 = 666.

It is a tau number, because it is divible by the number of its divisors (144).

It is a junction number, because it is equal to n+sod(n) for n = 21125758698 and 21125758707.

It is not an unprimeable number, because it can be changed into a prime (21125758751) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2598598 + ... + 2606714.

It is an arithmetic number, because the mean of its divisors is an integer number (477224748).

Almost surely, 2^21125758752 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21125758752, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34360181856).

21125758752 is an abundant number, since it is smaller than the sum of its proper divisors (47594604960).

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

21125758752 is a wasteful number, since it uses less digits than its factorization.

21125758752 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9431 (or 9420 counting only the distinct ones).

The product of its digits is 392000, while the sum is 45.

The spelling of 21125758752 in words is "twenty-one billion, one hundred twenty-five million, seven hundred fifty-eight thousand, seven hundred fifty-two".