18791479709 has 2 divisors, whose sum is σ = 18791479710. Its totient is φ = 18791479708.

The previous prime is 18791479691. The next prime is 18791479813. The reversal of 18791479709 is 90797419781.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15722652100 + 3068827609 = 125390^2 + 55397^2 .

It is a cyclic number.

It is not a de Polignac number, because 18791479709 - 2⁸ = 18791479453 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18791449709) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9395739854 + 9395739855.

It is an arithmetic number, because the mean of its divisors is an integer number (9395739855).

Almost surely, 2^18791479709 is an apocalyptic number.

It is an amenable number.

18791479709 is a deficient number, since it is larger than the sum of its proper divisors (1).

18791479709 is an equidigital number, since it uses as much as digits as its factorization.

18791479709 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8001504, while the sum is 62.

The spelling of 18791479709 in words is "eighteen billion, seven hundred ninety-one million, four hundred seventy-nine thousand, seven hundred nine".