18157201 has 4 divisors (see below), whose sum is σ = 18428272. Its totient is φ = 17886132.

The previous prime is 18157187. The next prime is 18157211. The reversal of 18157201 is 10275181.

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.

It is a cyclic number.

It is not a de Polignac number, because 18157201 - 2⁵ = 18157169 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18157211) 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, 135435 + ... + 135568.

It is an arithmetic number, because the mean of its divisors is an integer number (4607068).

Almost surely, 2^18157201 is an apocalyptic number.

It is an amenable number.

18157201 is a deficient number, since it is larger than the sum of its proper divisors (271071).

18157201 is an equidigital number, since it uses as much as digits as its factorization.

18157201 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 271070.

The product of its (nonzero) digits is 560, while the sum is 25.

The square root of 18157201 is about 4261.1267289298. The cubic root of 18157201 is about 262.8348609336.

The spelling of 18157201 in words is "eighteen million, one hundred fifty-seven thousand, two hundred one".