99997 has 6 divisors (see below), whose sum is σ = 105918. Its totient is φ = 94392.

The previous prime is 99991. The next prime is 100003. The reversal of 99997 is 79999.

It is an interprime number because it is at equal distance from previous prime (99991) and next prime (100003).

It can be written as a sum of positive squares in only one way, i.e., 70756 + 29241 = 266^2 + 171^2 .

It is not a de Polignac number, because 99997 - 2³ = 99989 is a prime.

It is a Duffinian number.

It is a nialpdrome in base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (99991) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 223 + ... + 499.

It is an arithmetic number, because the mean of its divisors is an integer number (17653).

2⁹⁹⁹⁹⁷ is an apocalyptic number.

It is an amenable number.

99997 is a deficient number, since it is larger than the sum of its proper divisors (5921).

99997 is a wasteful number, since it uses less digits than its factorization.

99997 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 315 (or 296 counting only the distinct ones).

The product of its digits is 45927, while the sum is 43.

The square root of 99997 is about 316.2230225648. The cubic root of 99997 is about 46.4154241726.

Adding to 99997 its product of digits (45927), we get a square (145924 = 382²).

The spelling of 99997 in words is "ninety-nine thousand, nine hundred ninety-seven".