121242409 has 2 divisors, whose sum is σ = 121242410. Its totient is φ = 121242408.

The previous prime is 121242391. The next prime is 121242427. The reversal of 121242409 is 904242121.

It is a balanced prime because it is at equal distance from previous prime (121242391) and next prime (121242427).

It can be written as a sum of positive squares in only one way, i.e., 121066009 + 176400 = 11003^2 + 420^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-121242409 is a prime.

It is not a weakly prime, because it can be changed into another prime (121242809) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60621204 + 60621205.

It is an arithmetic number, because the mean of its divisors is an integer number (60621205).

Almost surely, 2^121242409 is an apocalyptic number.

It is an amenable number.

121242409 is a deficient number, since it is larger than the sum of its proper divisors (1).

121242409 is an equidigital number, since it uses as much as digits as its factorization.

121242409 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1152, while the sum is 25.

The square root of 121242409 is about 11011.0130778235. The cubic root of 121242409 is about 494.9388204496.

It can be divided in two parts, 12 and 1242409, that added together give a palindrome (1242421).

The spelling of 121242409 in words is "one hundred twenty-one million, two hundred forty-two thousand, four hundred nine".