999647993 has 2 divisors, whose sum is σ = 999647994. Its totient is φ = 999647992.

The previous prime is 999647983. The next prime is 999648061. The reversal of 999647993 is 399746999.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 797667049 + 201980944 = 28243^2 + 14212^2 .

It is an emirp because it is prime and its reverse (399746999) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 999647993 - 2²² = 995453689 is a prime.

It is a super-2 number, since 2×999647993² = 1998592219817856098, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (999647983) 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, 499823996 + 499823997.

It is an arithmetic number, because the mean of its divisors is an integer number (499823997).

Almost surely, 2^999647993 is an apocalyptic number.

It is an amenable number.

999647993 is a deficient number, since it is larger than the sum of its proper divisors (1).

999647993 is an equidigital number, since it uses as much as digits as its factorization.

999647993 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 29760696, while the sum is 65.

The square root of 999647993 is about 31617.2103924429. The cubic root of 999647993 is about 999.8826505630.

The spelling of 999647993 in words is "nine hundred ninety-nine million, six hundred forty-seven thousand, nine hundred ninety-three".