655040 has 56 divisors (see below), whose sum is σ = 1645920. Its totient is φ = 247808.

The previous prime is 655037. The next prime is 655043. The reversal of 655040 is 40556.

655040 = T₂₈₈ + T₂₈₉ + ... + T₃₀₂.

It is an interprime number because it is at equal distance from previous prime (655037) and next prime (655043).

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

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 655040.

It is not an unprimeable number, because it can be changed into a prime (655043) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 7316 + ... + 7404.

2⁶⁵⁵⁰⁴⁰ 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 655040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (822960).

655040 is an abundant number, since it is smaller than the sum of its proper divisors (990880).

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

655040 is a wasteful number, since it uses less digits than its factorization.

655040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 129 (or 119 counting only the distinct ones).

The product of its (nonzero) digits is 600, while the sum is 20.

The square root of 655040 is about 809.3454145172. The cubic root of 655040 is about 86.8472238376.

Adding to 655040 its reverse (40556), we get a palindrome (695596).

The spelling of 655040 in words is "six hundred fifty-five thousand, forty".