655645 has 4 divisors (see below), whose sum is σ = 786780. Its totient is φ = 524512.

The previous prime is 655643. The next prime is 655649. The reversal of 655645 is 546556.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 383161 + 272484 = 619^2 + 522^2 .

It is a cyclic number.

It is not a de Polignac number, because 655645 - 2¹ = 655643 is a prime.

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (655643) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 65560 + ... + 65569.

It is an arithmetic number, because the mean of its divisors is an integer number (196695).

2⁶⁵⁵⁶⁴⁵ is an apocalyptic number.

It is an amenable number.

655645 is a deficient number, since it is larger than the sum of its proper divisors (131135).

655645 is a wasteful number, since it uses less digits than its factorization.

655645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 131134.

The product of its digits is 18000, while the sum is 31.

The square root of 655645 is about 809.7190870913. The cubic root of 655645 is about 86.8739531989.

The spelling of 655645 in words is "six hundred fifty-five thousand, six hundred forty-five".