999983947 has 2 divisors, whose sum is σ = 999983948. Its totient is φ = 999983946.

The previous prime is 999983923. The next prime is 999983989. The reversal of 999983947 is 749389999.

It is a weak prime.

It is an emirp because it is prime and its reverse (749389999) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 999983947 - 2⁷ = 999983819 is a prime.

It is not a weakly prime, because it can be changed into another prime (999953947) 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, 499991973 + 499991974.

It is an arithmetic number, because the mean of its divisors is an integer number (499991974).

Almost surely, 2^999983947 is an apocalyptic number.

999983947 is a deficient number, since it is larger than the sum of its proper divisors (1).

999983947 is an equidigital number, since it uses as much as digits as its factorization.

999983947 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 39680928, while the sum is 67.

The square root of 999983947 is about 31622.5227804487. The cubic root of 999983947 is about 999.9946489714.

The spelling of 999983947 in words is "nine hundred ninety-nine million, nine hundred eighty-three thousand, nine hundred forty-seven".