655540 has 24 divisors (see below), whose sum is σ = 1398600. Its totient is φ = 258048.

The previous prime is 655531. The next prime is 655541. The reversal of 655540 is 45556.

It can be written as a sum of positive squares in 4 ways, for example, as 104976 + 550564 = 324^2 + 742^2 .

It is a nialpdrome in base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (655541) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1236 + ... + 1684.

It is an arithmetic number, because the mean of its divisors is an integer number (58275).

2⁶⁵⁵⁵⁴⁰ is an apocalyptic number.

It is an amenable number.

655540 is an abundant number, since it is smaller than the sum of its proper divisors (743060).

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

655540 is a wasteful number, since it uses less digits than its factorization.

655540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 531 (or 529 counting only the distinct ones).

The product of its (nonzero) digits is 3000, while the sum is 25.

The square root of 655540 is about 809.6542471944. The cubic root of 655540 is about 86.8693153984.

The spelling of 655540 in words is "six hundred fifty-five thousand, five hundred forty".