21501527005056 has 128 divisors (see below), whose sum is σ = 67036614428160. Its totient is φ = 5977258444800.

The previous prime is 21501527005051. The next prime is 21501527005061. The reversal of 21501527005056 is 65050072510512.

It is an interprime number because it is at equal distance from previous prime (21501527005051) and next prime (21501527005061).

It is a tau number, because it is divible by the number of its divisors (128).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21501527005051) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 107996220 + ... + 108195131.

It is an arithmetic number, because the mean of its divisors is an integer number (523723550220).

Almost surely, 2^{21501527005056} is an apocalyptic number.

It is an amenable number.

21501527005056 is an abundant number, since it is smaller than the sum of its proper divisors (45535087423104).

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

21501527005056 is a wasteful number, since it uses less digits than its factorization.

21501527005056 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 216191412 (or 216191400 counting only the distinct ones).

The product of its (nonzero) digits is 105000, while the sum is 39.

Adding to 21501527005056 its reverse (65050072510512), we get a palindrome (86551599515568).

The spelling of 21501527005056 in words is "twenty-one trillion, five hundred one billion, five hundred twenty-seven million, five thousand, fifty-six".