18747 has 6 divisors (see below), whose sum is σ = 27092. Its totient is φ = 12492.

The previous prime is 18743. The next prime is 18749. The reversal of 18747 is 74781.

Added to its reverse (74781) it gives a triangular number (93528 = T₄₃₂).

18747 is digitally balanced in base 3 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 18747 - 2² = 18743 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

18747 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 18747.

It is not an unprimeable number, because it can be changed into a prime (18743) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1033 + ... + 1050.

2¹⁸⁷⁴⁷ is an apocalyptic number.

18747 is a deficient number, since it is larger than the sum of its proper divisors (8345).

18747 is a wasteful number, since it uses less digits than its factorization.

18747 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2089 (or 2086 counting only the distinct ones).

The product of its digits is 1568, while the sum is 27.

The square root of 18747 is about 136.9196844869. The cubic root of 18747 is about 26.5650472759.

Adding to 18747 its reverse (74781), we get a triangular number (93528 = T₄₃₂).

It can be divided in two parts, 1874 and 7, that added together give a palindrome (1881).

The spelling of 18747 in words is "eighteen thousand, seven hundred forty-seven".