9998777813 has 2 divisors, whose sum is σ = 9998777814. Its totient is φ = 9998777812.

The previous prime is 9998777809. The next prime is 9998777837. The reversal of 9998777813 is 3187778999.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 8560320484 + 1438457329 = 92522^2 + 37927^2 .

It is a cyclic number.

It is not a de Polignac number, because 9998777813 - 2² = 9998777809 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (9998777513) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4999388906 + 4999388907.

It is an arithmetic number, because the mean of its divisors is an integer number (4999388907).

Almost surely, 2^9998777813 is an apocalyptic number.

It is an amenable number.

9998777813 is a deficient number, since it is larger than the sum of its proper divisors (1).

9998777813 is an equidigital number, since it uses as much as digits as its factorization.

9998777813 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 48009024, while the sum is 68.

The square root of 9998777813 is about 99993.8888782710. Note that the first 4 decimals coincide. The cubic root of 9998777813 is about 2154.3469157202.

The spelling of 9998777813 in words is "nine billion, nine hundred ninety-eight million, seven hundred seventy-seven thousand, eight hundred thirteen".