12121234223661 has 12 divisors (see below), whose sum is σ = 17548332012640. Its totient is φ = 8062415471880.

The previous prime is 12121234223599. The next prime is 12121234223687. The reversal of 12121234223661 is 16632243212121.

It is a happy number.

12121234223661 is a `hidden beast` number, since 1 + 2 + 1 + 21 + 2 + 342 + 236 + 61 = 666.

It is not a de Polignac number, because 12121234223661 - 2³⁰ = 12120160481837 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 (12121234323661) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1533941155 + ... + 1533949056.

Almost surely, 2^{12121234223661} is an apocalyptic number.

It is an amenable number.

12121234223661 is a deficient number, since it is larger than the sum of its proper divisors (5427097788979).

12121234223661 is a wasteful number, since it uses less digits than its factorization.

12121234223661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3067890656 (or 3067890653 counting only the distinct ones).

The product of its digits is 41472, while the sum is 36.

Adding to 12121234223661 its reverse (16632243212121), we get a palindrome (28753477435782).

The spelling of 12121234223661 in words is "twelve trillion, one hundred twenty-one billion, two hundred thirty-four million, two hundred twenty-three thousand, six hundred sixty-one".