121111021 has 2 divisors, whose sum is σ = 121111022. Its totient is φ = 121111020.

The previous prime is 121110991. The next prime is 121111037. The reversal of 121111021 is 120111121.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 115885225 + 5225796 = 10765^2 + 2286^2 .

It is a cyclic number.

It is not a de Polignac number, because 121111021 - 2¹³ = 121102829 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 121110989 and 121111007.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (121111051) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60555510 + 60555511.

It is an arithmetic number, because the mean of its divisors is an integer number (60555511).

Almost surely, 2^121111021 is an apocalyptic number.

It is an amenable number.

121111021 is a deficient number, since it is larger than the sum of its proper divisors (1).

121111021 is an equidigital number, since it uses as much as digits as its factorization.

121111021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4, while the sum is 10.

The square root of 121111021 is about 11005.0452520651. The cubic root of 121111021 is about 494.7599706927.

Adding to 121111021 its reverse (120111121), we get a palindrome (241222142).

The spelling of 121111021 in words is "one hundred twenty-one million, one hundred eleven thousand, twenty-one".