18522389 has 4 divisors (see below), whose sum is σ = 18640524. Its totient is φ = 18404256.

The previous prime is 18522377. The next prime is 18522421. The reversal of 18522389 is 98322581.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 98322581 = 7 ⋅14046083.

It can be written as a sum of positive squares in 2 ways, for example, as 2079364 + 16443025 = 1442^2 + 4055^2 .

It is a cyclic number.

It is not a de Polignac number, because 18522389 - 2²⁴ = 1745173 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 (18522349) 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, 58832 + ... + 59145.

It is an arithmetic number, because the mean of its divisors is an integer number (4660131).

Almost surely, 2^18522389 is an apocalyptic number.

It is an amenable number.

18522389 is a deficient number, since it is larger than the sum of its proper divisors (118135).

18522389 is a wasteful number, since it uses less digits than its factorization.

18522389 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 118134.

The product of its digits is 34560, while the sum is 38.

The square root of 18522389 is about 4303.7645149334. The cubic root of 18522389 is about 264.5852727298.

The spelling of 18522389 in words is "eighteen million, five hundred twenty-two thousand, three hundred eighty-nine".