121211020111 has 4 divisors (see below), whose sum is σ = 121217975424. Its totient is φ = 121204064800.

The previous prime is 121211020093. The next prime is 121211020141. The reversal of 121211020111 is 111020112121.

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: 111020112121 = 71 ⋅1563663551.

It is a cyclic number.

It is not a de Polignac number, because 121211020111 - 2⁵ = 121211020079 is a prime.

It is a super-2 number, since 2×121211020111² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 121211020091 and 121211020100.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121211020141) 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, 3451450 + ... + 3486391.

It is an arithmetic number, because the mean of its divisors is an integer number (30304493856).

Almost surely, 2^121211020111 is an apocalyptic number.

121211020111 is a deficient number, since it is larger than the sum of its proper divisors (6955313).

121211020111 is an equidigital number, since it uses as much as digits as its factorization.

121211020111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6955312.

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

Adding to 121211020111 its reverse (111020112121), we get a palindrome (232231132232).

The spelling of 121211020111 in words is "one hundred twenty-one billion, two hundred eleven million, twenty thousand, one hundred eleven".