999995813 has 2 divisors, whose sum is σ = 999995814. Its totient is φ = 999995812.

The previous prime is 999995809. The next prime is 999995819. The reversal of 999995813 is 318599999.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 955613569 + 44382244 = 30913^2 + 6662^2 .

It is a cyclic number.

It is not a de Polignac number, because 999995813 - 2² = 999995809 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 (999995819) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 499997906 + 499997907.

It is an arithmetic number, because the mean of its divisors is an integer number (499997907).

Almost surely, 2^999995813 is an apocalyptic number.

It is an amenable number.

999995813 is a deficient number, since it is larger than the sum of its proper divisors (1).

999995813 is an equidigital number, since it uses as much as digits as its factorization.

999995813 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7085880, while the sum is 62.

The square root of 999995813 is about 31622.7103993317. The cubic root of 999995813 is about 999.9986043314.

The spelling of 999995813 in words is "nine hundred ninety-nine million, nine hundred ninety-five thousand, eight hundred thirteen".