121221212111 has 8 divisors (see below), whose sum is σ = 125150005248. Its totient is φ = 117293571000.

The previous prime is 121221212081. The next prime is 121221212131. The reversal of 121221212111 is 111212122121.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-121221212111 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 121221212111.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121221212131) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 71555 + ... + 497556.

It is an arithmetic number, because the mean of its divisors is an integer number (15643750656).

Almost surely, 2^121221212111 is an apocalyptic number.

121221212111 is a deficient number, since it is larger than the sum of its proper divisors (3928793137).

121221212111 is an equidigital number, since it uses as much as digits as its factorization.

121221212111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 576013.

The product of its digits is 32, while the sum is 17.

Adding to 121221212111 its reverse (111212122121), we get a palindrome (232433334232).

The spelling of 121221212111 in words is "one hundred twenty-one billion, two hundred twenty-one million, two hundred twelve thousand, one hundred eleven".