655780 has 12 divisors (see below), whose sum is σ = 1377180. Its totient is φ = 262304.

The previous prime is 655757. The next prime is 655807. The reversal of 655780 is 87556.

It can be written as a sum of positive squares in 2 ways, for example, as 278784 + 376996 = 528^2 + 614^2 .

It is an Ulam number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16375 + ... + 16414.

It is an arithmetic number, because the mean of its divisors is an integer number (114765).

2⁶⁵⁵⁷⁸⁰ is an apocalyptic number.

It is an amenable number.

655780 is an abundant number, since it is smaller than the sum of its proper divisors (721400).

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

655780 is a wasteful number, since it uses less digits than its factorization.

655780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32798 (or 32796 counting only the distinct ones).

The product of its (nonzero) digits is 8400, while the sum is 31.

The square root of 655780 is about 809.8024450445. The cubic root of 655780 is about 86.8799153577.

The spelling of 655780 in words is "six hundred fifty-five thousand, seven hundred eighty".