12121891636 has 12 divisors (see below), whose sum is σ = 21664657728. Its totient is φ = 5931989432.

The previous prime is 12121891619. The next prime is 12121891673. The reversal of 12121891636 is 63619812121.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 32238886 + ... + 32239261.

It is an arithmetic number, because the mean of its divisors is an integer number (1805388144).

Almost surely, 2^12121891636 is an apocalyptic number.

It is an amenable number.

12121891636 is a deficient number, since it is larger than the sum of its proper divisors (9542766092).

12121891636 is a wasteful number, since it uses less digits than its factorization.

12121891636 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 64478198 (or 64478196 counting only the distinct ones).

The product of its digits is 31104, while the sum is 40.

The spelling of 12121891636 in words is "twelve billion, one hundred twenty-one million, eight hundred ninety-one thousand, six hundred thirty-six".