18130565 has 4 divisors (see below), whose sum is σ = 21756684. Its totient is φ = 14504448.

The previous prime is 18130559. The next prime is 18130583. The reversal of 18130565 is 56503181.

It is a Cunningham number, because it is equal to 4258²+1.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 6522916 + 11607649 = 2554^2 + 3407^2 .

It is a cyclic number.

It is not a de Polignac number, because 18130565 - 2⁸ = 18130309 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1813052 + ... + 1813061.

It is an arithmetic number, because the mean of its divisors is an integer number (5439171).

Almost surely, 2^18130565 is an apocalyptic number.

It is an amenable number.

18130565 is a deficient number, since it is larger than the sum of its proper divisors (3626119).

18130565 is an equidigital number, since it uses as much as digits as its factorization.

18130565 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3626118.

The product of its (nonzero) digits is 3600, while the sum is 29.

The square root of 18130565 is about 4258.0001174260. Note that the first 3 decimals coincide. The cubic root of 18130565 is about 262.7062747509.

The spelling of 18130565 in words is "eighteen million, one hundred thirty thousand, five hundred sixty-five".