20121221110101 has 16 divisors (see below), whose sum is σ = 26910343796544. Its totient is φ = 13373136520064.

The previous prime is 20121221110037. The next prime is 20121221110121. The reversal of 20121221110101 is 10101112212102.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 20121221110101 - 2⁶ = 20121221110037 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20121221110121) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4228825 + ... + 7624001.

It is an arithmetic number, because the mean of its divisors is an integer number (1681896487284).

Almost surely, 2^{20121221110101} is an apocalyptic number.

It is an amenable number.

20121221110101 is a deficient number, since it is larger than the sum of its proper divisors (6789122686443).

20121221110101 is a wasteful number, since it uses less digits than its factorization.

20121221110101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3401220.

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 20121221110101 its reverse (10101112212102), we get a palindrome (30222333322203).

The spelling of 20121221110101 in words is "twenty trillion, one hundred twenty-one billion, two hundred twenty-one million, one hundred ten thousand, one hundred one".