21520534250250 has 192 divisors, whose sum is σ = 66523563774720. Its totient is φ = 4917576585600.

The previous prime is 21520534250203. The next prime is 21520534250261. The reversal of 21520534250250 is 5205243502512.

21520534250250 is a `hidden beast` number, since 2 + 1 + 5 + 20 + 534 + 2 + 50 + 2 + 50 = 666.

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, 55546204 + ... + 55932296.

It is an arithmetic number, because the mean of its divisors is an integer number (346476894660).

Almost surely, 2^{21520534250250} is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21520534250250, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33261781887360).

21520534250250 is an abundant number, since it is smaller than the sum of its proper divisors (45003029524470).

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

21520534250250 is a wasteful number, since it uses less digits than its factorization.

21520534250250 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 389662 (or 389649 counting only the distinct ones).

The product of its (nonzero) digits is 120000, while the sum is 36.

Adding to 21520534250250 its reverse (5205243502512), we get a palindrome (26725777752762).

The spelling of 21520534250250 in words is "twenty-one trillion, five hundred twenty billion, five hundred thirty-four million, two hundred fifty thousand, two hundred fifty".