121111211021 has 4 divisors (see below), whose sum is σ = 126376915872. Its totient is φ = 115845506172.

The previous prime is 121111211009. The next prime is 121111211047. The reversal of 121111211021 is 120112111121.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 121111211021 - 2¹⁴ = 121111194637 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 121111210987 and 121111211005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121111211051) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2632852391 + ... + 2632852436.

It is an arithmetic number, because the mean of its divisors is an integer number (31594228968).

Almost surely, 2^121111211021 is an apocalyptic number.

It is an amenable number.

121111211021 is a deficient number, since it is larger than the sum of its proper divisors (5265704851).

121111211021 is an equidigital number, since it uses as much as digits as its factorization.

121111211021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5265704850.

The product of its (nonzero) digits is 8, while the sum is 14.

Adding to 121111211021 its reverse (120112111121), we get a palindrome (241223322142).

The spelling of 121111211021 in words is "one hundred twenty-one billion, one hundred eleven million, two hundred eleven thousand, twenty-one".