18132557 has 4 divisors (see below), whose sum is σ = 19199196. Its totient is φ = 17065920.

The previous prime is 18132539. The next prime is 18132559. The reversal of 18132557 is 75523181.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 75523181 = 4111 ⋅18371.

It can be written as a sum of positive squares in 2 ways, for example, as 11062276 + 7070281 = 3326^2 + 2659^2 .

It is a cyclic number.

It is not a de Polignac number, because 18132557 - 2¹⁴ = 18116173 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 (18132559) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 533294 + ... + 533327.

It is an arithmetic number, because the mean of its divisors is an integer number (4799799).

Almost surely, 2^18132557 is an apocalyptic number.

18132557 is a gapful number since it is divisible by the number (17) formed by its first and last digit.

It is an amenable number.

18132557 is a deficient number, since it is larger than the sum of its proper divisors (1066639).

18132557 is a wasteful number, since it uses less digits than its factorization.

18132557 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1066638.

The product of its digits is 8400, while the sum is 32.

The square root of 18132557 is about 4258.2340236300. The cubic root of 18132557 is about 262.7158955531.

The spelling of 18132557 in words is "eighteen million, one hundred thirty-two thousand, five hundred fifty-seven".