21125441403712 has 112 divisors (see below), whose sum is σ = 43343318494800. Its totient is φ = 10208176422912.

The previous prime is 21125441403707. The next prime is 21125441403721. The reversal of 21125441403712 is 21730414452112.

It can be written as a sum of positive squares in 8 ways, for example, as 5501951949376 + 15623489454336 = 2345624^2 + 3952656^2 .

It is a Harshad number since it is a multiple of its sum of digits (37).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1268863164 + ... + 1268879812.

Almost surely, 2^{21125441403712} 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 21125441403712, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21671659247400).

21125441403712 is an abundant number, since it is smaller than the sum of its proper divisors (22217877091088).

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

21125441403712 is a wasteful number, since it uses less digits than its factorization.

21125441403712 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20268 (or 20258 counting only the distinct ones).

The product of its (nonzero) digits is 53760, while the sum is 37.

Adding to 21125441403712 its reverse (21730414452112), we get a palindrome (42855855855824).

The spelling of 21125441403712 in words is "twenty-one trillion, one hundred twenty-five billion, four hundred forty-one million, four hundred three thousand, seven hundred twelve".