997799 has 4 divisors (see below), whose sum is σ = 1088520. Its totient is φ = 907080.

The previous prime is 997793. The next prime is 997807.

997799 is nontrivially palindromic in base 10.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 997799 - 2⁴ = 997783 is a prime.

It is a Duffinian number.

It is a zygodrome in base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (997793) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 45344 + ... + 45365.

It is an arithmetic number, because the mean of its divisors is an integer number (272130).

2⁹⁹⁷⁷⁹⁹ is an apocalyptic number.

997799 is a deficient number, since it is larger than the sum of its proper divisors (90721).

997799 is a wasteful number, since it uses less digits than its factorization.

997799 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 90720.

The product of its digits is 321489, while the sum is 50.

The square root of 997799 is about 998.8988937825. The cubic root of 997799 is about 99.9265794407.

The spelling of 997799 in words is "nine hundred ninety-seven thousand, seven hundred ninety-nine".