121211100221111 has 8 divisors (see below), whose sum is σ = 122344542552960. Its totient is φ = 120081392461368.

The previous prime is 121211100221063. The next prime is 121211100221129. The reversal of 121211100221111 is 111122001112121.

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

It is a cyclic number.

It is not a de Polignac number, because 121211100221111 - 2¹⁸ = 121211099958967 is a prime.

It is a super-4 number, since 4×121211100221111⁴ (a number of 57 digits) contains 4444 as substring. Note that it is a super-d number also for d = 2.

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 121211100221111.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121211100221411) 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, 933577811 + ... + 933707636.

It is an arithmetic number, because the mean of its divisors is an integer number (15293067819120).

Almost surely, 2^{121211100221111} is an apocalyptic number.

121211100221111 is a deficient number, since it is larger than the sum of its proper divisors (1133442331849).

121211100221111 is a wasteful number, since it uses less digits than its factorization.

121211100221111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1867286053.

The product of its (nonzero) digits is 16, while the sum is 17.

Adding to 121211100221111 its reverse (111122001112121), we get a palindrome (232333101333232).

The spelling of 121211100221111 in words is "one hundred twenty-one trillion, two hundred eleven billion, one hundred million, two hundred twenty-one thousand, one hundred eleven".