998951609 has 2 divisors, whose sum is σ = 998951610.
Its totient is φ = 998951608.
The previous prime is 998951587. The next prime is 998951623. The reversal of 998951609 is 906159899.
It is a strong prime.
It can be written as a sum of positive squares in only one way, i.e., 809971600 + 188980009 = 28460^2 + 13747^2
It is an emirp because it is prime and its reverse (906159899) is a distict prime.
It is a cyclic number.
It is not a de Polignac number, because 998951609 - 220 = 997903033 is a prime.
It is not a weakly prime, because it can be changed into another prime (998951689) by changing a digit.
It is a pernicious number, because its binary representation contains a prime number (17) of ones.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 499475804 + 499475805.
It is an arithmetic number, because the mean of its divisors is an integer number (499475805).
Almost surely, 2998951609 is an apocalyptic number.
It is an amenable number.
998951609 is a deficient number, since it is larger than the sum of its proper divisors (1).
998951609 is an equidigital number, since it uses as much as digits as its factorization.
998951609 is an odious number, because the sum of its binary digits is odd.
The product of its (nonzero) digits is 1574640, while the sum is 56.
The square root of 998951609 is about 31606.1957375449.
The cubic root of 998951609 is about 999.6504141373.
The spelling of 998951609 in words is "nine hundred ninety-eight million, nine hundred fifty-one thousand, six hundred nine".