8218255509 has 24 divisors (see below), whose sum is σ = 12286909440. Its totient is φ = 5287000992.

The previous prime is 8218255499. The next prime is 8218255523. The reversal of 8218255509 is 9055528128.

It is a happy number.

8218255509 is a `hidden beast` number, since 82 + 18 + 2 + 5 + 550 + 9 = 666.

It is not a de Polignac number, because 8218255509 - 2²³ = 8209866901 is a prime.

It is a super-2 number, since 2×8218255509² (a number of 21 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8218255909) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 530812 + ... + 546074.

It is an arithmetic number, because the mean of its divisors is an integer number (511954560).

Almost surely, 2^8218255509 is an apocalyptic number.

It is an amenable number.

8218255509 is a deficient number, since it is larger than the sum of its proper divisors (4068653931).

8218255509 is a wasteful number, since it uses less digits than its factorization.

8218255509 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17361 (or 17358 counting only the distinct ones).

The product of its (nonzero) digits is 288000, while the sum is 45.

The square root of 8218255509 is about 90654.5945278010. The cubic root of 8218255509 is about 2018.0250203741.

The spelling of 8218255509 in words is "eight billion, two hundred eighteen million, two hundred fifty-five thousand, five hundred nine".