656040 has 128 divisors (see below), whose sum is σ = 2488320. Its totient is φ = 134400.

The previous prime is 656039. The next prime is 656063. The reversal of 656040 is 40656.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a junction number, because it is equal to n+sod(n) for n = 655998 and 656016.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 9205 + ... + 9275.

It is an arithmetic number, because the mean of its divisors is an integer number (19440).

2⁶⁵⁶⁰⁴⁰ is an apocalyptic number.

656040 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 656040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1244160).

656040 is an abundant number, since it is smaller than the sum of its proper divisors (1832280).

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

656040 is a wasteful number, since it uses less digits than its factorization.

656040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 103 (or 99 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 21.

The square root of 656040 is about 809.9629621162. The cubic root of 656040 is about 86.8913957289.

Adding to 656040 its reverse (40656), we get a palindrome (696696).

It can be divided in two parts, 65 and 6040, that added together give a triangular number (6105 = T₁₁₀).

The spelling of 656040 in words is "six hundred fifty-six thousand, forty".