18901 has 4 divisors (see below), whose sum is σ = 19404. Its totient is φ = 18400.

The previous prime is 18899. The next prime is 18911. The reversal of 18901 is 10981.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 10981 = 79 ⋅139.

It can be written as a sum of positive squares in 2 ways, for example, as 3025 + 15876 = 55^2 + 126^2 .

It is a cyclic number.

It is not a de Polignac number, because 18901 - 2¹ = 18899 is a prime.

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

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18911) 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, 190 + ... + 271.

It is an arithmetic number, because the mean of its divisors is an integer number (4851).

2¹⁸⁹⁰¹ is an apocalyptic number.

It is an amenable number.

18901 is a deficient number, since it is larger than the sum of its proper divisors (503).

18901 is an equidigital number, since it uses as much as digits as its factorization.

18901 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 502.

The product of its (nonzero) digits is 72, while the sum is 19.

The square root of 18901 is about 137.4809077654. The cubic root of 18901 is about 26.6375898345.

It can be divided in two parts, 1890 and 1, that added together give a triangular number (1891 = T₆₁).

The spelling of 18901 in words is "eighteen thousand, nine hundred one".