655616 has 36 divisors (see below), whose sum is σ = 1416492. Its totient is φ = 301056.

The previous prime is 655601. The next prime is 655637. The reversal of 655616 is 616556.

It can be written as a sum of positive squares in 2 ways, for example, as 409600 + 246016 = 640^2 + 496^2 .

It is an unprimeable number.

655616 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (3) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3230 + ... + 3426.

It is an arithmetic number, because the mean of its divisors is an integer number (39347).

2⁶⁵⁵⁶¹⁶ 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 655616, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (708246).

655616 is an abundant number, since it is smaller than the sum of its proper divisors (760876).

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

655616 is a wasteful number, since it uses less digits than its factorization.

655616 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 226 (or 212 counting only the distinct ones).

The product of its digits is 5400, while the sum is 29.

The square root of 655616 is about 809.7011794483. The cubic root of 655616 is about 86.8726723321.

Subtracting from 655616 its reverse (616556), we obtain a triangular number (39060 = T₂₇₉).

The spelling of 655616 in words is "six hundred fifty-five thousand, six hundred sixteen".