121212220221111 has 8 divisors (see below), whose sum is σ = 161624305223920. Its totient is φ = 80804141016192.

The previous prime is 121212220221083. The next prime is 121212220221133. The reversal of 121212220221111 is 111122022212121.

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

It is not a de Polignac number, because 121212220221111 - 2⁹ = 121212220220599 is a prime.

It is a super-4 number, since 4×121212220221111⁴ (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 congruent number.

It is not an unprimeable number, because it can be changed into a prime (121212220221511) 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, 1001378866 + ... + 1001499903.

It is an arithmetic number, because the mean of its divisors is an integer number (20203038152990).

Almost surely, 2^{121212220221111} is an apocalyptic number.

121212220221111 is a deficient number, since it is larger than the sum of its proper divisors (40412085002809).

121212220221111 is a wasteful number, since it uses less digits than its factorization.

121212220221111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2002898945.

The product of its (nonzero) digits is 128, while the sum is 21.

Adding to 121212220221111 its reverse (111122022212121), we get a palindrome (232334242433232).

The spelling of 121212220221111 in words is "one hundred twenty-one trillion, two hundred twelve billion, two hundred twenty million, two hundred twenty-one thousand, one hundred eleven".