20110121210121 has 4 divisors (see below), whose sum is σ = 26813494946832. Its totient is φ = 13406747473412.

The previous prime is 20110121210111. The next prime is 20110121210141. The reversal of 20110121210121 is 12101212101102.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 20110121210121 - 2⁹ = 20110121209609 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20110121210121.

It is not an unprimeable number, because it can be changed into a prime (20110121210111) 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, 3351686868351 + ... + 3351686868356.

It is an arithmetic number, because the mean of its divisors is an integer number (6703373736708).

Almost surely, 2^{20110121210121} is an apocalyptic number.

It is an amenable number.

20110121210121 is a deficient number, since it is larger than the sum of its proper divisors (6703373736711).

20110121210121 is an equidigital number, since it uses as much as digits as its factorization.

20110121210121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6703373736710.

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

Adding to 20110121210121 its reverse (12101212101102), we get a palindrome (32211333311223).

The spelling of 20110121210121 in words is "twenty trillion, one hundred ten billion, one hundred twenty-one million, two hundred ten thousand, one hundred twenty-one".