18428533 has 4 divisors (see below), whose sum is σ = 18495340. Its totient is φ = 18361728.

The previous prime is 18428519. The next prime is 18428549. The reversal of 18428533 is 33582481.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 33582481 = 19 ⋅1767499.

It can be written as a sum of positive squares in 2 ways, for example, as 9199089 + 9229444 = 3033^2 + 3038^2 .

It is a cyclic number.

It is not a de Polignac number, because 18428533 - 2¹³ = 18420341 is a prime.

It is a super-2 number, since 2×18428533² = 679221657064178, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18428513) 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, 32988 + ... + 33541.

It is an arithmetic number, because the mean of its divisors is an integer number (4623835).

Almost surely, 2^18428533 is an apocalyptic number.

It is an amenable number.

18428533 is a deficient number, since it is larger than the sum of its proper divisors (66807).

18428533 is an equidigital number, since it uses as much as digits as its factorization.

18428533 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66806.

The product of its digits is 23040, while the sum is 34.

The square root of 18428533 is about 4292.8467244941. The cubic root of 18428533 is about 264.1376166888.

The spelling of 18428533 in words is "eighteen million, four hundred twenty-eight thousand, five hundred thirty-three".