21501445045055 has 32 divisors (see below), whose sum is σ = 26071957651968. Its totient is φ = 17021510553600.

The previous prime is 21501445045019. The next prime is 21501445045063. The reversal of 21501445045055 is 55054054410512.

It is not a de Polignac number, because 21501445045055 - 2²⁰ = 21501443996479 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2476835315 + ... + 2476843995.

It is an arithmetic number, because the mean of its divisors is an integer number (814748676624).

Almost surely, 2^{21501445045055} is an apocalyptic number.

21501445045055 is a deficient number, since it is larger than the sum of its proper divisors (4570512606913).

21501445045055 is a wasteful number, since it uses less digits than its factorization.

21501445045055 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15347.

The product of its (nonzero) digits is 400000, while the sum is 41.

Adding to 21501445045055 its reverse (55054054410512), we get a palindrome (76555499455567).

The spelling of 21501445045055 in words is "twenty-one trillion, five hundred one billion, four hundred forty-five million, forty-five thousand, fifty-five".