18972201 has 4 divisors (see below), whose sum is σ = 25296272. Its totient is φ = 12648132.

The previous prime is 18972199. The next prime is 18972229. The reversal of 18972201 is 10227981.

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 not a de Polignac number, because 18972201 - 2¹ = 18972199 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18972271) 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, 3162031 + ... + 3162036.

It is an arithmetic number, because the mean of its divisors is an integer number (6324068).

Almost surely, 2^18972201 is an apocalyptic number.

It is an amenable number.

18972201 is a deficient number, since it is larger than the sum of its proper divisors (6324071).

18972201 is an equidigital number, since it uses as much as digits as its factorization.

18972201 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6324070.

The product of its (nonzero) digits is 2016, while the sum is 30.

The square root of 18972201 is about 4355.7090123193. The cubic root of 18972201 is about 266.7099629353.

It can be divided in two parts, 189 and 72201, that added together give a triangular number (72390 = T₃₈₀).

The spelling of 18972201 in words is "eighteen million, nine hundred seventy-two thousand, two hundred one".