978609 has 4 divisors (see below), whose sum is σ = 1304816. Its totient is φ = 652404.

The previous prime is 978599. The next prime is 978611. The reversal of 978609 is 906879.

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 not a de Polignac number, because 978609 - 2¹¹ = 976561 is a prime.

It is a D-number.

It is a Duffinian number.

It is a nialpdrome in base 16.

It is not an unprimeable number, because it can be changed into a prime (978619) 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, 163099 + ... + 163104.

It is an arithmetic number, because the mean of its divisors is an integer number (326204).

2⁹⁷⁸⁶⁰⁹ is an apocalyptic number.

It is an amenable number.

978609 is a deficient number, since it is larger than the sum of its proper divisors (326207).

978609 is a wasteful number, since it uses less digits than its factorization.

978609 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 326206.

The product of its (nonzero) digits is 27216, while the sum is 39.

The square root of 978609 is about 989.2466830877. The cubic root of 978609 is about 99.2818212063.

The spelling of 978609 in words is "nine hundred seventy-eight thousand, six hundred nine".