16555224204121 has 4 divisors (see below), whose sum is σ = 16590980628352. Its totient is φ = 16519467779892.

The previous prime is 16555224204083. The next prime is 16555224204173. The reversal of 16555224204121 is 12140242255561.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 16555224204121 - 2²³ = 16555215815513 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16555224204191) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 17878211421 + ... + 17878212346.

It is an arithmetic number, because the mean of its divisors is an integer number (4147745157088).

Almost surely, 2^{16555224204121} is an apocalyptic number.

It is an amenable number.

16555224204121 is a deficient number, since it is larger than the sum of its proper divisors (35756424231).

16555224204121 is an equidigital number, since it uses as much as digits as its factorization.

16555224204121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35756424230.

The product of its (nonzero) digits is 192000, while the sum is 40.

Adding to 16555224204121 its reverse (12140242255561), we get a palindrome (28695466459682).

It can be divided in two parts, 16555 and 224204121, that added together give a square (224220676 = 14974²).

The spelling of 16555224204121 in words is "sixteen trillion, five hundred fifty-five billion, two hundred twenty-four million, two hundred four thousand, one hundred twenty-one".