999999999997 has 4 divisors (see below), whose sum is σ = 1000181592576. Its totient is φ = 999818407420.

The previous prime is 999999999989. The next prime is 1000000000039. The reversal of 999999999997 is 799999999999.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 999999999997 - 2³ = 999999999989 is a prime.

It is a super-9 number, since 9×999999999997⁹ (a number of 109 digits) contains 999999999 as substring.

It is a Duffinian number.

It is a nialpdrome in base 10.

It is a self number, because there is not a number n which added to its sum of digits gives 999999999997.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (999999999937) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 90788029 + ... + 90799042.

It is an arithmetic number, because the mean of its divisors is an integer number (250045398144).

Almost surely, 2^999999999997 is an apocalyptic number.

It is an amenable number.

999999999997 is a deficient number, since it is larger than the sum of its proper divisors (181592579).

999999999997 is a wasteful number, since it uses less digits than its factorization.

999999999997 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 181592578.

The product of its digits is 219667417263, while the sum is 106.

The spelling of 999999999997 in words is "nine hundred ninety-nine billion, nine hundred ninety-nine million, nine hundred ninety-nine thousand, nine hundred ninety-seven".