12205311556 has 24 divisors (see below), whose sum is σ = 21510856640. Its totient is φ = 6059424672.

The previous prime is 12205311553. The next prime is 12205311563. The reversal of 12205311556 is 65511350221.

It is a super-2 number, since 2×12205311556² (a number of 21 digits) contains 22 as substring.

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

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 719905 + ... + 736663.

Almost surely, 2^12205311556 is an apocalyptic number.

It is an amenable number.

12205311556 is a deficient number, since it is larger than the sum of its proper divisors (9305545084).

12205311556 is a wasteful number, since it uses less digits than its factorization.

12205311556 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18043 (or 18041 counting only the distinct ones).

The product of its (nonzero) digits is 9000, while the sum is 31.

Adding to 12205311556 its reverse (65511350221), we get a palindrome (77716661777).

It can be divided in two parts, 12205 and 311556, that added together give a square (323761 = 569²).

The spelling of 12205311556 in words is "twelve billion, two hundred five million, three hundred eleven thousand, five hundred fifty-six".