1298805817 has 2 divisors, whose sum is σ = 1298805818. Its totient is φ = 1298805816.

The previous prime is 1298805799. The next prime is 1298805821. The reversal of 1298805817 is 7185088921.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1298593296 + 212521 = 36036^2 + 461^2 .

It is an emirp because it is prime and its reverse (7185088921) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1298805817 - 2¹¹ = 1298803769 is a prime.

It is not a weakly prime, because it can be changed into another prime (1298805877) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 649402908 + 649402909.

It is an arithmetic number, because the mean of its divisors is an integer number (649402909).

Almost surely, 2^1298805817 is an apocalyptic number.

It is an amenable number.

1298805817 is a deficient number, since it is larger than the sum of its proper divisors (1).

1298805817 is an equidigital number, since it uses as much as digits as its factorization.

1298805817 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 322560, while the sum is 49.

The square root of 1298805817 is about 36038.9486111901. The cubic root of 1298805817 is about 1091.0585953407.

The spelling of 1298805817 in words is "one billion, two hundred ninety-eight million, eight hundred five thousand, eight hundred seventeen".