11212120111 has 4 divisors (see below), whose sum is σ = 11212589224. Its totient is φ = 11211651000.

The previous prime is 11212120091. The next prime is 11212120133. The reversal of 11212120111 is 11102121211.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 11102121211 = 19 ⋅584322169.

It is a cyclic number.

It is not a de Polignac number, because 11212120111 - 2⁵ = 11212120079 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 11212120091 and 11212120100.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11212120411) 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, 196665 + ... + 247186.

It is an arithmetic number, because the mean of its divisors is an integer number (2803147306).

Almost surely, 2^11212120111 is an apocalyptic number.

11212120111 is a deficient number, since it is larger than the sum of its proper divisors (469113).

11212120111 is an equidigital number, since it uses as much as digits as its factorization.

11212120111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 469112.

The product of its (nonzero) digits is 8, while the sum is 13.

Adding to 11212120111 its reverse (11102121211), we get a palindrome (22314241322).

The spelling of 11212120111 in words is "eleven billion, two hundred twelve million, one hundred twenty thousand, one hundred eleven".