18008834809 has 27 divisors (see below), whose sum is σ = 22131599247. Its totient is φ = 14609222208.

The previous prime is 18008834807. The next prime is 18008834819. The reversal of 18008834809 is 90843880081.

The square root of 18008834809 is 134197.

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

It can be written as a sum of positive squares in only one way, i.e., 5527476409 + 12481358400 = 74347^2 + 111720^2 .

It is not a de Polignac number, because 18008834809 - 2¹ = 18008834807 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (49).

It is not an unprimeable number, because it can be changed into a prime (18008834801) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 17847697 + ... + 17848705.

It is an arithmetic number, because the mean of its divisors is an integer number (819688861).

Almost surely, 2^18008834809 is an apocalyptic number.

18008834809 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

18008834809 is the 134197-th square number.

18008834809 is the 67099-th centered octagonal number.

It is an amenable number.

18008834809 is a deficient number, since it is larger than the sum of its proper divisors (4122764438).

18008834809 is an frugal number, since it uses more digits than its factorization.

18008834809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2070 (or 1035 counting only the distinct ones).

The product of its (nonzero) digits is 442368, while the sum is 49.

Multiplying 18008834809 by its sum of digits (49), we get a square (882432905641 = 939379²).

18008834809 divided by its sum of digits (49) gives a square (367527241 = 19171²).

The spelling of 18008834809 in words is "eighteen billion, eight million, eight hundred thirty-four thousand, eight hundred nine".