817997 has 4 divisors (see below), whose sum is σ = 844416. Its totient is φ = 791580.

The previous prime is 817987. The next prime is 818011. The reversal of 817997 is 799718.

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 817997 - 2⁶ = 817933 is a prime.

It is a Duffinian number.

It is a zygodrome in base 7.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (817907) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13163 + ... + 13224.

It is an arithmetic number, because the mean of its divisors is an integer number (211104).

2⁸¹⁷⁹⁹⁷ is an apocalyptic number.

It is an amenable number.

817997 is a deficient number, since it is larger than the sum of its proper divisors (26419).

817997 is a wasteful number, since it uses less digits than its factorization.

817997 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26418.

The product of its digits is 31752, while the sum is 41.

The square root of 817997 is about 904.4318658694. The cubic root of 817997 is about 93.5227431877.

The spelling of 817997 in words is "eight hundred seventeen thousand, nine hundred ninety-seven".