18489397 has 4 divisors (see below), whose sum is σ = 18723520. Its totient is φ = 18255276.

The previous prime is 18489391. The next prime is 18489403. The reversal of 18489397 is 79398481.

It is a happy number.

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 an interprime number because it is at equal distance from previous prime (18489391) and next prime (18489403).

It is a cyclic number.

It is not a de Polignac number, because 18489397 - 2³ = 18489389 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 18489397.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18489391) 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, 116943 + ... + 117100.

It is an arithmetic number, because the mean of its divisors is an integer number (4680880).

Almost surely, 2^18489397 is an apocalyptic number.

It is an amenable number.

18489397 is a deficient number, since it is larger than the sum of its proper divisors (234123).

18489397 is an equidigital number, since it uses as much as digits as its factorization.

18489397 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 234122.

The product of its digits is 435456, while the sum is 49.

The square root of 18489397 is about 4299.9298831493. The cubic root of 18489397 is about 264.4280866481.

The spelling of 18489397 in words is "eighteen million, four hundred eighty-nine thousand, three hundred ninety-seven".