999666413 has 2 divisors, whose sum is σ = 999666414. Its totient is φ = 999666412.

The previous prime is 999666389. The next prime is 999666431. The reversal of 999666413 is 314666999.

Together with next prime (999666431) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 805537924 + 194128489 = 28382^2 + 13933^2 .

It is a cyclic number.

It is not a de Polignac number, because 999666413 - 2¹⁰ = 999665389 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (999666463) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 499833206 + 499833207.

It is an arithmetic number, because the mean of its divisors is an integer number (499833207).

Almost surely, 2^999666413 is an apocalyptic number.

It is an amenable number.

999666413 is a deficient number, since it is larger than the sum of its proper divisors (1).

999666413 is an equidigital number, since it uses as much as digits as its factorization.

999666413 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1889568, while the sum is 53.

The square root of 999666413 is about 31617.5016881473. The cubic root of 999666413 is about 999.8887919666. Note that the first 3 decimals are identical.

The spelling of 999666413 in words is "nine hundred ninety-nine million, six hundred sixty-six thousand, four hundred thirteen".