7942247809 has 2 divisors, whose sum is σ = 7942247810. Its totient is φ = 7942247808.

The previous prime is 7942247749. The next prime is 7942247851. The reversal of 7942247809 is 9087422497.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 4754516209 + 3187731600 = 68953^2 + 56460^2 .

It is an emirp because it is prime and its reverse (9087422497) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 7942247809 - 2⁹ = 7942247297 is a prime.

It is not a weakly prime, because it can be changed into another prime (7942247899) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3971123904 + 3971123905.

It is an arithmetic number, because the mean of its divisors is an integer number (3971123905).

Almost surely, 2^7942247809 is an apocalyptic number.

It is an amenable number.

7942247809 is a deficient number, since it is larger than the sum of its proper divisors (1).

7942247809 is an equidigital number, since it uses as much as digits as its factorization.

7942247809 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2032128, while the sum is 52.

The square root of 7942247809 is about 89119.2897693872. The cubic root of 7942247809 is about 1995.1756897889.

The spelling of 7942247809 in words is "seven billion, nine hundred forty-two million, two hundred forty-seven thousand, eight hundred nine".