18424389 has 4 divisors (see below), whose sum is σ = 24565856. Its totient is φ = 12282924.

The previous prime is 18424381. The next prime is 18424411. The reversal of 18424389 is 98342481.

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.

It is not a de Polignac number, because 18424389 - 2³ = 18424381 is a prime.

It is a super-2 number, since 2×18424389² = 678916220046642, 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 (18424381) 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, 3070729 + ... + 3070734.

It is an arithmetic number, because the mean of its divisors is an integer number (6141464).

Almost surely, 2^18424389 is an apocalyptic number.

It is an amenable number.

18424389 is a deficient number, since it is larger than the sum of its proper divisors (6141467).

18424389 is an equidigital number, since it uses as much as digits as its factorization.

18424389 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6141466.

The product of its digits is 55296, while the sum is 39.

The square root of 18424389 is about 4292.3640339561. The cubic root of 18424389 is about 264.1178164449.

The spelling of 18424389 in words is "eighteen million, four hundred twenty-four thousand, three hundred eighty-nine".