12100001221 has 32 divisors (see below), whose sum is σ = 15511781376. Its totient is φ = 9164016000.

The previous prime is 12100001203. The next prime is 12100001233. The reversal of 12100001221 is 12210000121.

It is a cyclic number.

It is not a de Polignac number, because 12100001221 - 2¹¹ = 12099999173 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 12100001198 and 12100001207.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12100001261) 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 31 ways as a sum of consecutive naturals, for example, 848476 + ... + 862618.

It is an arithmetic number, because the mean of its divisors is an integer number (484743168).

Almost surely, 2^12100001221 is an apocalyptic number.

12100001221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

12100001221 is a deficient number, since it is larger than the sum of its proper divisors (3411780155).

12100001221 is a wasteful number, since it uses less digits than its factorization.

12100001221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14473.

The product of its (nonzero) digits is 8, while the sum is 10.

Adding to 12100001221 its reverse (12210000121), we get a palindrome (24310001342).

The spelling of 12100001221 in words is "twelve billion, one hundred million, one thousand, two hundred twenty-one".