18532790509 has 4 divisors (see below), whose sum is σ = 18702816220. Its totient is φ = 18362764800.

The previous prime is 18532790501. The next prime is 18532790531. The reversal of 18532790509 is 90509723581.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 90509723581 = 953 ⋅94973477.

It can be written as a sum of positive squares in 2 ways, for example, as 13559438025 + 4973352484 = 116445^2 + 70522^2 .

It is a cyclic number.

It is not a de Polignac number, because 18532790509 - 2³ = 18532790501 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18532790501) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 85012692 + ... + 85012909.

It is an arithmetic number, because the mean of its divisors is an integer number (4675704055).

Almost surely, 2^18532790509 is an apocalyptic number.

It is an amenable number.

18532790509 is a deficient number, since it is larger than the sum of its proper divisors (170025711).

18532790509 is a wasteful number, since it uses less digits than its factorization.

18532790509 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 170025710.

The product of its (nonzero) digits is 680400, while the sum is 49.

The spelling of 18532790509 in words is "eighteen billion, five hundred thirty-two million, seven hundred ninety thousand, five hundred nine".