20101121211111 has 4 divisors (see below), whose sum is σ = 26801494948152. Its totient is φ = 13400747474072.

The previous prime is 20101121211049. The next prime is 20101121211133. The reversal of 20101121211111 is 11111212110102.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20101121211111 - 2⁷ = 20101121210983 is a prime.

It is a super-3 number, since 3×20101121211111³ (a number of 41 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20101121211181) 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 3 ways as a sum of consecutive naturals, for example, 3350186868516 + ... + 3350186868521.

It is an arithmetic number, because the mean of its divisors is an integer number (6700373737038).

Almost surely, 2^{20101121211111} is an apocalyptic number.

20101121211111 is a deficient number, since it is larger than the sum of its proper divisors (6700373737041).

20101121211111 is an equidigital number, since it uses as much as digits as its factorization.

20101121211111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6700373737040.

The product of its (nonzero) digits is 8, while the sum is 15.

Adding to 20101121211111 its reverse (11111212110102), we get a palindrome (31212333321213).

It can be divided in two parts, 2010112 and 1211111, that added together give a palindrome (3221223).

The spelling of 20101121211111 in words is "twenty trillion, one hundred one billion, one hundred twenty-one million, two hundred eleven thousand, one hundred eleven".