18540362569 has 3 divisors (see below), whose sum is σ = 18540498733. Its totient is φ = 18540226406.

The previous prime is 18540362531. The next prime is 18540362591. The reversal of 18540362569 is 96526304581.

The square root of 18540362569 is 136163.

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

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 96526304581 = 7 ⋅13789472083.

It is not a de Polignac number, because 18540362569 - 2⁷ = 18540362441 is a prime.

It is a super-2 number, since 2×18540362569² (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 (18540369569) 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 2 ways as a sum of consecutive naturals, for example, 68082 + ... + 204244.

Almost surely, 2^18540362569 is an apocalyptic number.

18540362569 is the 136163-rd square number.

18540362569 is the 68082-nd centered octagonal number.

It is an amenable number.

18540362569 is a deficient number, since it is larger than the sum of its proper divisors (136164).

18540362569 is an frugal number, since it uses more digits than its factorization.

18540362569 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 272326 (or 136163 counting only the distinct ones).

The product of its (nonzero) digits is 1555200, while the sum is 49.

Multiplying 18540362569 by its sum of digits (49), we get a square (908477765881 = 953141²).

The spelling of 18540362569 in words is "eighteen billion, five hundred forty million, three hundred sixty-two thousand, five hundred sixty-nine".