1242112409 has 2 divisors, whose sum is σ = 1242112410. Its totient is φ = 1242112408.

The previous prime is 1242112387. The next prime is 1242112477. The reversal of 1242112409 is 9042112421.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 724686400 + 517426009 = 26920^2 + 22747^2 .

It is an emirp because it is prime and its reverse (9042112421) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1242112409 - 2¹² = 1242108313 is a prime.

It is not a weakly prime, because it can be changed into another prime (1242112609) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 621056204 + 621056205.

It is an arithmetic number, because the mean of its divisors is an integer number (621056205).

Almost surely, 2^1242112409 is an apocalyptic number.

It is an amenable number.

1242112409 is a deficient number, since it is larger than the sum of its proper divisors (1).

1242112409 is an equidigital number, since it uses as much as digits as its factorization.

1242112409 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1152, while the sum is 26.

The square root of 1242112409 is about 35243.6151522513. The cubic root of 1242112409 is about 1074.9467892176.

The spelling of 1242112409 in words is "one billion, two hundred forty-two million, one hundred twelve thousand, four hundred nine".