18089557 has 4 divisors (see below), whose sum is σ = 18098080. Its totient is φ = 18081036.

The previous prime is 18089551. The next prime is 18089563. The reversal of 18089557 is 75598081.

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 a brilliant number, because the two primes have the same length.

It is an interprime number because it is at equal distance from previous prime (18089551) and next prime (18089563).

It is a cyclic number.

It is not a de Polignac number, because 18089557 - 2⁷ = 18089429 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 (18089551) 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, 1744 + ... + 6262.

It is an arithmetic number, because the mean of its divisors is an integer number (4524520).

Almost surely, 2^18089557 is an apocalyptic number.

It is an amenable number.

18089557 is a deficient number, since it is larger than the sum of its proper divisors (8523).

18089557 is an equidigital number, since it uses as much as digits as its factorization.

18089557 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8522.

The product of its (nonzero) digits is 100800, while the sum is 43.

The square root of 18089557 is about 4253.1819852905. The cubic root of 18089557 is about 262.5080608258.

The spelling of 18089557 in words is "eighteen million, eighty-nine thousand, five hundred fifty-seven".