18581201 has 4 divisors (see below), whose sum is σ = 18835812. Its totient is φ = 18326592.

The previous prime is 18581191. The next prime is 18581207. The reversal of 18581201 is 10218581.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 10218581 = 17 ⋅601093.

It can be written as a sum of positive squares in 2 ways, for example, as 12816400 + 5764801 = 3580^2 + 2401^2 .

It is a cyclic number.

It is not a de Polignac number, because 18581201 - 2¹⁸ = 18319057 is a prime.

It is a super-2 number, since 2×18581201² = 690522061204802, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (18581207) 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, 127196 + ... + 127341.

It is an arithmetic number, because the mean of its divisors is an integer number (4708953).

Almost surely, 2^18581201 is an apocalyptic number.

It is an amenable number.

18581201 is a deficient number, since it is larger than the sum of its proper divisors (254611).

18581201 is an equidigital number, since it uses as much as digits as its factorization.

18581201 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 254610.

The product of its (nonzero) digits is 640, while the sum is 26.

The square root of 18581201 is about 4310.5917227221. The cubic root of 18581201 is about 264.8650125372.

Adding to 18581201 its reverse (10218581), we get a palindrome (28799782).

The spelling of 18581201 in words is "eighteen million, five hundred eighty-one thousand, two hundred one".