630640 has 20 divisors (see below), whose sum is σ = 1466424. Its totient is φ = 252224.

The previous prime is 630613. The next prime is 630659. The reversal of 630640 is 46036.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (20).

It is a congruent 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 3 ways as a sum of consecutive naturals, for example, 3862 + ... + 4021.

2⁶³⁰⁶⁴⁰ is an apocalyptic number.

It is an amenable number.

630640 is an abundant number, since it is smaller than the sum of its proper divisors (835784).

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

630640 is a wasteful number, since it uses less digits than its factorization.

630640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7896 (or 7890 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 19.

The square root of 630640 is about 794.1284530855. The cubic root of 630640 is about 85.7552079728.

Adding to 630640 its reverse (46036), we get a palindrome (676676).

The spelling of 630640 in words is "six hundred thirty thousand, six hundred forty".