609640 has 16 divisors (see below), whose sum is σ = 1371780. Its totient is φ = 243840.

The previous prime is 609619. The next prime is 609641. The reversal of 609640 is 46906.

It can be written as a sum of positive squares in 2 ways, for example, as 605284 + 4356 = 778^2 + 66^2 .

It is not an unprimeable number, because it can be changed into a prime (609641) by changing a digit.

609640 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7581 + ... + 7660.

2⁶⁰⁹⁶⁴⁰ is an apocalyptic number.

It is an amenable number.

609640 is an abundant number, since it is smaller than the sum of its proper divisors (762140).

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

609640 is a wasteful number, since it uses less digits than its factorization.

609640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15252 (or 15248 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 25.

The square root of 609640 is about 780.7944671935. The cubic root of 609640 is about 84.7925738127.

The spelling of 609640 in words is "six hundred nine thousand, six hundred forty".