121111421 has 2 divisors, whose sum is σ = 121111422. Its totient is φ = 121111420.

The previous prime is 121111409. The next prime is 121111427. The reversal of 121111421 is 124111121.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 116402521 + 4708900 = 10789^2 + 2170^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-121111421 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 121111396 and 121111405.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (121111427) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60555710 + 60555711.

It is an arithmetic number, because the mean of its divisors is an integer number (60555711).

Almost surely, 2^121111421 is an apocalyptic number.

It is an amenable number.

121111421 is a deficient number, since it is larger than the sum of its proper divisors (1).

121111421 is an equidigital number, since it uses as much as digits as its factorization.

121111421 is an evil number, because the sum of its binary digits is even.

The product of its digits is 16, while the sum is 14.

The square root of 121111421 is about 11005.0634255328. The cubic root of 121111421 is about 494.7605153824.

Adding to 121111421 its reverse (124111121), we get a palindrome (245222542).

The spelling of 121111421 in words is "one hundred twenty-one million, one hundred eleven thousand, four hundred twenty-one".