654640 has 60 divisors (see below), whose sum is σ = 1781136. Its totient is φ = 223104.

The previous prime is 654629. The next prime is 654671. The reversal of 654640 is 46456.

It is a happy number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3837 + ... + 4003.

2⁶⁵⁴⁶⁴⁰ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 654640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (890568).

654640 is an abundant number, since it is smaller than the sum of its proper divisors (1126496).

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

654640 is a wasteful number, since it uses less digits than its factorization.

654640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 194 (or 181 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 25.

The square root of 654640 is about 809.0982635008. The cubic root of 654640 is about 86.8295424935.

The spelling of 654640 in words is "six hundred fifty-four thousand, six hundred forty".