999997173 has 12 divisors (see below), whose sum is σ = 1650789088. Its totient is φ = 571426920.

The previous prime is 999997133. The next prime is 999997181. The reversal of 999997173 is 371799999.

It is not a de Polignac number, because 999997173 - 2¹⁰ = 999996149 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (63), and also a Moran number because the ratio is a prime number: 15872971 = 999997173 / (9 + 9 + 9 + 9 + 9 + 7 + 1 + 7 + 3).

It is a nude number because it is divisible by every one of its digits.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 999997173.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (999997133) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 7936423 + ... + 7936548.

Almost surely, 2^999997173 is an apocalyptic number.

It is an amenable number.

999997173 is a deficient number, since it is larger than the sum of its proper divisors (650791915).

999997173 is a wasteful number, since it uses less digits than its factorization.

999997173 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15872984 (or 15872981 counting only the distinct ones).

The product of its digits is 8680203, while the sum is 63.

The square root of 999997173 is about 31622.7319028575. The cubic root of 999997173 is about 999.9990576658. Note that the first 3 decimals are identical.

The spelling of 999997173 in words is "nine hundred ninety-nine million, nine hundred ninety-seven thousand, one hundred seventy-three".