18641 has 4 divisors (see below), whose sum is σ = 21312. Its totient is φ = 15972.

The previous prime is 18637. The next prime is 18661. The reversal of 18641 is 14681.

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 an emirpimes, since its reverse is a distinct semiprime: 14681 = 53 ⋅277.

It is a cyclic number.

It is not a de Polignac number, because 18641 - 2² = 18637 is a prime.

It is a Duffinian number.

It is a nialpdrome in base 8 and base 12.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 18641.

It is not an unprimeable number, because it can be changed into a prime (18661) 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, 1325 + ... + 1338.

It is an arithmetic number, because the mean of its divisors is an integer number (5328).

2¹⁸⁶⁴¹ is an apocalyptic number.

It is an amenable number.

18641 is a deficient number, since it is larger than the sum of its proper divisors (2671).

18641 is an equidigital number, since it uses as much as digits as its factorization.

18641 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2670.

The product of its digits is 192, while the sum is 20.

The square root of 18641 is about 136.5320475200. The cubic root of 18641 is about 26.5148842455.

It can be divided in two parts, 186 and 41, that multiplied together give a triangular number (7626 = T₁₂₃).

The spelling of 18641 in words is "eighteen thousand, six hundred forty-one".