1999999913 has 2 divisors, whose sum is σ = 1999999914. Its totient is φ = 1999999912.

The previous prime is 1999999873. The next prime is 1999999927. The reversal of 1999999913 is 3199999991.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1998805264 + 1194649 = 44708^2 + 1093^2 .

It is a cyclic number.

It is not a de Polignac number, because 1999999913 - 2⁸ = 1999999657 is a prime.

It is not a weakly prime, because it can be changed into another prime (1999999943) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 999999956 + 999999957.

It is an arithmetic number, because the mean of its divisors is an integer number (999999957).

Almost surely, 2^1999999913 is an apocalyptic number.

It is an amenable number.

1999999913 is a deficient number, since it is larger than the sum of its proper divisors (1).

1999999913 is an equidigital number, since it uses as much as digits as its factorization.

1999999913 is an evil number, because the sum of its binary digits is even.

The product of its digits is 14348907, while the sum is 68.

The square root of 1999999913 is about 44721.3585773062. The cubic root of 1999999913 is about 1259.9210316260.

The spelling of 1999999913 in words is "one billion, nine hundred ninety-nine million, nine hundred ninety-nine thousand, nine hundred thirteen".