655427209 has 4 divisors (see below), whose sum is σ = 655652116. Its totient is φ = 655202304.

The previous prime is 655427183. The next prime is 655427221. The reversal of 655427209 is 902724556.

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 223951225 + 431475984 = 14965^2 + 20772^2 .

It is a cyclic number.

It is not a de Polignac number, because 655427209 - 2⁷ = 655427081 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (655427009) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 108024 + ... + 113929.

It is an arithmetic number, because the mean of its divisors is an integer number (163913029).

Almost surely, 2^655427209 is an apocalyptic number.

It is an amenable number.

655427209 is a deficient number, since it is larger than the sum of its proper divisors (224907).

655427209 is a wasteful number, since it uses less digits than its factorization.

655427209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 224906.

The product of its (nonzero) digits is 151200, while the sum is 40.

The square root of 655427209 is about 25601.3126421283. The cubic root of 655427209 is about 868.6433292143.

The spelling of 655427209 in words is "six hundred fifty-five million, four hundred twenty-seven thousand, two hundred nine".