20111101212121 has 4 divisors (see below), whose sum is σ = 20759846412544. Its totient is φ = 19462356011700.

The previous prime is 20111101212109. The next prime is 20111101212131. The reversal of 20111101212121 is 12121210111102.

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 20111101212121 - 2¹⁵ = 20111101179353 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20111101212095 and 20111101212104.

It is not an unprimeable number, because it can be changed into a prime (20111101212131) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 324372600165 + ... + 324372600226.

It is an arithmetic number, because the mean of its divisors is an integer number (5189961603136).

Almost surely, 2^{20111101212121} is an apocalyptic number.

It is an amenable number.

20111101212121 is a deficient number, since it is larger than the sum of its proper divisors (648745200423).

20111101212121 is an equidigital number, since it uses as much as digits as its factorization.

20111101212121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 648745200422.

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

Adding to 20111101212121 its reverse (12121210111102), we get a palindrome (32232311323223).

The spelling of 20111101212121 in words is "twenty trillion, one hundred eleven billion, one hundred one million, two hundred twelve thousand, one hundred twenty-one".