12103551221 has 4 divisors (see below), whose sum is σ = 12105609612. Its totient is φ = 12101492832.

The previous prime is 12103551203. The next prime is 12103551307. The reversal of 12103551221 is 12215530121.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 6867436900 + 5236114321 = 82870^2 + 72361^2 .

It is a cyclic number.

It is not a de Polignac number, because 12103551221 - 2¹⁴ = 12103534837 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12103251221) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1020350 + ... + 1032143.

It is an arithmetic number, because the mean of its divisors is an integer number (3026402403).

Almost surely, 2^12103551221 is an apocalyptic number.

It is an amenable number.

12103551221 is a deficient number, since it is larger than the sum of its proper divisors (2058391).

12103551221 is an equidigital number, since it uses as much as digits as its factorization.

12103551221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2058390.

The product of its (nonzero) digits is 600, while the sum is 23.

The spelling of 12103551221 in words is "twelve billion, one hundred three million, five hundred fifty-one thousand, two hundred twenty-one".