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18437 = 103179

18437 has 4 divisors (see below), whose sum is σ = 18720. Its totient is φ = 18156.

The previous prime is 18433. The next prime is 18439. The reversal of 18437 is 73481.

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, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 73481 = 197373.

It is a cyclic number.

It is not a de Polignac number, because 18437 - 22 = 18433 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 18437.

It is not an unprimeable number, because it can be changed into a prime (18433) 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, 14 + ... + 192.

It is an arithmetic number, because the mean of its divisors is an integer number (4680).

218437 is an apocalyptic number.

It is an amenable number.

18437 is a deficient number, since it is larger than the sum of its proper divisors (283).

18437 is a wasteful number, since it uses less digits than its factorization.

18437 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 282.

The product of its digits is 672, while the sum is 23.

The square root of 18437 is about 135.7829149783. The cubic root of 18437 is about 26.4178063221.

The spelling of 18437 in words is "eighteen thousand, four hundred thirty-seven".

Divisors: 1 103 179 18437