18010445209 has 9 divisors (see below), whose sum is σ = 18444943359. Its totient is φ = 17585961120.

The previous prime is 18010445161. The next prime is 18010445231. The reversal of 18010445209 is 90254401081.

It is a happy number.

The square root of 18010445209 is 134203.

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., 11539609 + 17998905600 = 3397^2 + 134160^2 .

It is not a de Polignac number, because 18010445209 - 2⁷ = 18010445081 is a prime.

It is a super-2 number, since 2×18010445209² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18010445309) 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, 5769169 + ... + 5772289.

It is an arithmetic number, because the mean of its divisors is an integer number (2049438151).

Almost surely, 2^18010445209 is an apocalyptic number.

18010445209 is the 134203-rd square number.

18010445209 is the 67102-nd centered octagonal number.

It is an amenable number.

18010445209 is a deficient number, since it is larger than the sum of its proper divisors (434498150).

18010445209 is an frugal number, since it uses more digits than its factorization.

18010445209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6328 (or 3164 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 34.

The spelling of 18010445209 in words is "eighteen billion, ten million, four hundred forty-five thousand, two hundred nine".