1242140509 has 2 divisors, whose sum is σ = 1242140510. Its totient is φ = 1242140508.

The previous prime is 1242140467. The next prime is 1242140539. The reversal of 1242140509 is 9050412421.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 993195225 + 248945284 = 31515^2 + 15778^2 .

It is a cyclic number.

It is not a de Polignac number, because 1242140509 - 2⁷ = 1242140381 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1242140539) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 621070254 + 621070255.

It is an arithmetic number, because the mean of its divisors is an integer number (621070255).

Almost surely, 2^1242140509 is an apocalyptic number.

It is an amenable number.

1242140509 is a deficient number, since it is larger than the sum of its proper divisors (1).

1242140509 is an equidigital number, since it uses as much as digits as its factorization.

1242140509 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2880, while the sum is 28.

The square root of 1242140509 is about 35244.0138037653. The cubic root of 1242140509 is about 1074.9548952411.

The spelling of 1242140509 in words is "one billion, two hundred forty-two million, one hundred forty thousand, five hundred nine".