999644071 has 2 divisors, whose sum is σ = 999644072. Its totient is φ = 999644070.

The previous prime is 999644069. The next prime is 999644153. The reversal of 999644071 is 170446999.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 999644071 - 2¹ = 999644069 is a prime.

Together with 999644069, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (999645071) 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, 499822035 + 499822036.

It is an arithmetic number, because the mean of its divisors is an integer number (499822036).

Almost surely, 2^999644071 is an apocalyptic number.

999644071 is a deficient number, since it is larger than the sum of its proper divisors (1).

999644071 is an equidigital number, since it uses as much as digits as its factorization.

999644071 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 489888, while the sum is 49.

The square root of 999644071 is about 31617.1483691999. The cubic root of 999644071 is about 999.8813429211.

The spelling of 999644071 in words is "nine hundred ninety-nine million, six hundred forty-four thousand, seventy-one".