18209542507 has 32 divisors (see below), whose sum is σ = 20520783360. Its totient is φ = 16044687360.

The previous prime is 18209542501. The next prime is 18209542513. The reversal of 18209542507 is 70524590281.

It is an interprime number because it is at equal distance from previous prime (18209542501) and next prime (18209542513).

It is not a de Polignac number, because 18209542507 - 2¹⁵ = 18209509739 is a prime.

It is a Smith number, since the sum of its digits (43) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18209542501) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 11288433 + ... + 11290045.

It is an arithmetic number, because the mean of its divisors is an integer number (641274480).

Almost surely, 2^18209542507 is an apocalyptic number.

18209542507 is a deficient number, since it is larger than the sum of its proper divisors (2311240853).

18209542507 is a wasteful number, since it uses less digits than its factorization.

18209542507 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2023.

The product of its (nonzero) digits is 201600, while the sum is 43.

The spelling of 18209542507 in words is "eighteen billion, two hundred nine million, five hundred forty-two thousand, five hundred seven".