97809 has 4 divisors (see below), whose sum is σ = 130416. Its totient is φ = 65204.

The previous prime is 97789. The next prime is 97813. The reversal of 97809 is 90879.

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, and also an emirpimes, since its reverse is a distinct semiprime: 90879 = 3 ⋅30293.

It is a cyclic number.

It is not a de Polignac number, because 97809 - 2⁵ = 97777 is a prime.

It is a D-number.

97809 is a lucky number.

It is a plaindrome in base 13.

It is a self number, because there is not a number n which added to its sum of digits gives 97809.

It is not an unprimeable number, because it can be changed into a prime (97829) 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, 16299 + ... + 16304.

It is an arithmetic number, because the mean of its divisors is an integer number (32604).

2⁹⁷⁸⁰⁹ is an apocalyptic number.

It is an amenable number.

97809 is a deficient number, since it is larger than the sum of its proper divisors (32607).

97809 is a wasteful number, since it uses less digits than its factorization.

97809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32606.

The product of its (nonzero) digits is 4536, while the sum is 33.

The square root of 97809 is about 312.7443045045. The cubic root of 97809 is about 46.0743912866.

The spelling of 97809 in words is "ninety-seven thousand, eight hundred nine".