999987847 has 2 divisors, whose sum is σ = 999987848. Its totient is φ = 999987846.

The previous prime is 999987829. The next prime is 999987871. The reversal of 999987847 is 748789999.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 999987847 - 2²⁷ = 865770119 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (999981847) 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, 499993923 + 499993924.

It is an arithmetic number, because the mean of its divisors is an integer number (499993924).

Almost surely, 2^999987847 is an apocalyptic number.

999987847 is a deficient number, since it is larger than the sum of its proper divisors (1).

999987847 is an equidigital number, since it uses as much as digits as its factorization.

999987847 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 82301184, while the sum is 70.

The square root of 999987847 is about 31622.5844452980. The cubic root of 999987847 is about 999.9959489836.

The spelling of 999987847 in words is "nine hundred ninety-nine million, nine hundred eighty-seven thousand, eight hundred forty-seven".