656109 has 6 divisors (see below), whose sum is σ = 947726. Its totient is φ = 437400.

The previous prime is 656077. The next prime is 656113. The reversal of 656109 is 901656.

656109 is a `hidden beast` number, since 656 + 1 + 0 + 9 = 666.

It can be written as a sum of positive squares in only one way, i.e., 656100 + 9 = 810^2 + 3^2 .

It is not a de Polignac number, because 656109 - 2⁵ = 656077 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (656119) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 36442 + ... + 36459.

2⁶⁵⁶¹⁰⁹ is an apocalyptic number.

It is an amenable number.

656109 is a deficient number, since it is larger than the sum of its proper divisors (291617).

656109 is a wasteful number, since it uses less digits than its factorization.

656109 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 72907 (or 72904 counting only the distinct ones).

The product of its (nonzero) digits is 1620, while the sum is 27.

The square root of 656109 is about 810.0055555365. The cubic root of 656109 is about 86.8944419334.

The spelling of 656109 in words is "six hundred fifty-six thousand, one hundred nine".