21544342130121 has 16 divisors (see below), whose sum is σ = 29985601236480. Its totient is φ = 13743400556160.

The previous prime is 21544342130107. The next prime is 21544342130149. The reversal of 21544342130121 is 12103124344512.

It is not a de Polignac number, because 21544342130121 - 2¹⁹ = 21544341605833 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21544342130191) 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, 1301450110 + ... + 1301466663.

It is an arithmetic number, because the mean of its divisors is an integer number (1874100077280).

Almost surely, 2^{21544342130121} is an apocalyptic number.

It is an amenable number.

21544342130121 is a deficient number, since it is larger than the sum of its proper divisors (8441259106359).

21544342130121 is a wasteful number, since it uses less digits than its factorization.

21544342130121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2602916896.

The product of its (nonzero) digits is 23040, while the sum is 33.

Adding to 21544342130121 its reverse (12103124344512), we get a palindrome (33647466474633).

The spelling of 21544342130121 in words is "twenty-one trillion, five hundred forty-four billion, three hundred forty-two million, one hundred thirty thousand, one hundred twenty-one".