121421221 has 2 divisors, whose sum is σ = 121421222. Its totient is φ = 121421220.

The previous prime is 121421197. The next prime is 121421227. The reversal of 121421221 is 122124121.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 70812225 + 50608996 = 8415^2 + 7114^2 .

It is a cyclic number.

It is not a de Polignac number, because 121421221 - 2⁵ = 121421189 is a prime.

It is a super-2 number, since 2×121421221² = 29486225818261682, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 121421195 and 121421204.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (121421227) 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 as a sum of consecutive naturals, namely, 60710610 + 60710611.

It is an arithmetic number, because the mean of its divisors is an integer number (60710611).

Almost surely, 2^121421221 is an apocalyptic number.

It is an amenable number.

121421221 is a deficient number, since it is larger than the sum of its proper divisors (1).

121421221 is an equidigital number, since it uses as much as digits as its factorization.

121421221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 64, while the sum is 16.

The square root of 121421221 is about 11019.1297750775. The cubic root of 121421221 is about 495.1820178828.

Adding to 121421221 its reverse (122124121), we get a palindrome (243545342).

The spelling of 121421221 in words is "one hundred twenty-one million, four hundred twenty-one thousand, two hundred twenty-one".