855387009 has 9 divisors (see below), whose sum is σ = 1235685763. Its totient is φ = 570199512.

The previous prime is 855386963. The next prime is 855387017. The reversal of 855387009 is 900783558.

The square root of 855387009 is 29247.

It is a perfect power (a square), and thus also a powerful number.

855387009 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 123143409 + 732243600 = 11097^2 + 27060^2 .

It is a tau number, because it is divible by the number of its divisors (9).

It is not a de Polignac number, because 855387009 - 2²³ = 846998401 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (855387019) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 82867 + ... + 92615.

Almost surely, 2^855387009 is an apocalyptic number.

855387009 is the 29247-th square number.

855387009 is the 14624-th centered octagonal number.

It is an amenable number.

855387009 is a deficient number, since it is larger than the sum of its proper divisors (380298754).

855387009 is an frugal number, since it uses more digits than its factorization.

855387009 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19504 (or 9752 counting only the distinct ones).

The product of its (nonzero) digits is 302400, while the sum is 45.

The cubic root of 855387009 is about 949.2651783944.

The spelling of 855387009 in words is "eight hundred fifty-five million, three hundred eighty-seven thousand, nine".