18530557 has 4 divisors (see below), whose sum is σ = 18596320. Its totient is φ = 18464796.

The previous prime is 18530537. The next prime is 18530573. The reversal of 18530557 is 75503581.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 75503581 = 271 ⋅278611.

It is a cyclic number.

It is not a de Polignac number, because 18530557 - 2¹⁵ = 18497789 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 (18530537) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 32457 + ... + 33022.

It is an arithmetic number, because the mean of its divisors is an integer number (4649080).

Almost surely, 2^18530557 is an apocalyptic number.

It is an amenable number.

18530557 is a deficient number, since it is larger than the sum of its proper divisors (65763).

18530557 is an equidigital number, since it uses as much as digits as its factorization.

18530557 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65762.

The product of its (nonzero) digits is 21000, while the sum is 34.

The square root of 18530557 is about 4304.7133470186. The cubic root of 18530557 is about 264.6241592708.

The spelling of 18530557 in words is "eighteen million, five hundred thirty thousand, five hundred fifty-seven".