18973271 has 4 divisors (see below), whose sum is σ = 19585344. Its totient is φ = 18361200.

The previous prime is 18973249. The next prime is 18973291. The reversal of 18973271 is 17237981.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 17237981 = 3167 ⋅5443.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18973271 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18973231) 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, 305990 + ... + 306051.

It is an arithmetic number, because the mean of its divisors is an integer number (4896336).

Almost surely, 2^18973271 is an apocalyptic number.

18973271 is a deficient number, since it is larger than the sum of its proper divisors (612073).

18973271 is an equidigital number, since it uses as much as digits as its factorization.

18973271 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 612072.

The product of its digits is 21168, while the sum is 38.

The square root of 18973271 is about 4355.8318378927. The cubic root of 18973271 is about 266.7149768377.

The spelling of 18973271 in words is "eighteen million, nine hundred seventy-three thousand, two hundred seventy-one".