609664 has 32 divisors (see below), whose sum is σ = 1328040. Its totient is φ = 276480.

The previous prime is 609641. The next prime is 609673. The reversal of 609664 is 466906.

It is a tau number, because it is divible by the number of its divisors (32).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1192 + ... + 1624.

2⁶⁰⁹⁶⁶⁴ is an apocalyptic number.

609664 is a gapful number since it is divisible by the number (64) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 609664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (664020).

609664 is an abundant number, since it is smaller than the sum of its proper divisors (718376).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

609664 is a wasteful number, since it uses less digits than its factorization.

609664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 458 (or 446 counting only the distinct ones).

The product of its (nonzero) digits is 7776, while the sum is 31.

The square root of 609664 is about 780.8098360036. The cubic root of 609664 is about 84.7936864885.

The spelling of 609664 in words is "six hundred nine thousand, six hundred sixty-four".