12205311555 has 16 divisors (see below), whose sum is σ = 19540734624. Its totient is φ = 6505420800.

The previous prime is 12205311553. The next prime is 12205311563. The reversal of 12205311555 is 55511350221.

It is not a de Polignac number, because 12205311555 - 2¹ = 12205311553 is a prime.

It is not an unprimeable number, because it can be changed into a prime (12205311553) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 230104 + ... + 278133.

It is an arithmetic number, because the mean of its divisors is an integer number (1221295914).

Almost surely, 2^12205311555 is an apocalyptic number.

12205311555 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

12205311555 is a deficient number, since it is larger than the sum of its proper divisors (7335423069).

12205311555 is a wasteful number, since it uses less digits than its factorization.

12205311555 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 509846.

The product of its (nonzero) digits is 7500, while the sum is 30.

Adding to 12205311555 its reverse (55511350221), we get a palindrome (67716661776).

The spelling of 12205311555 in words is "twelve billion, two hundred five million, three hundred eleven thousand, five hundred fifty-five".