635240 has 16 divisors (see below), whose sum is σ = 1429380. Its totient is φ = 254080.

The previous prime is 635207. The next prime is 635249. The reversal of 635240 is 42536.

It can be written as a sum of positive squares in 2 ways, for example, as 611524 + 23716 = 782^2 + 154^2 .

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (635249) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7901 + ... + 7980.

2⁶³⁵²⁴⁰ is an apocalyptic number.

It is an amenable number.

635240 is an abundant number, since it is smaller than the sum of its proper divisors (794140).

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

635240 is a wasteful number, since it uses less digits than its factorization.

635240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15892 (or 15888 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 20.

The square root of 635240 is about 797.0194476925. The cubic root of 635240 is about 85.9632076258.

Adding to 635240 its reverse (42536), we get a palindrome (677776).

Subtracting from 635240 its reverse (42536), we obtain a cube (592704 = 84³).

The spelling of 635240 in words is "six hundred thirty-five thousand, two hundred forty".