18444971 has 4 divisors (see below), whose sum is σ = 18468912. Its totient is φ = 18421032.

The previous prime is 18444967. The next prime is 18444989. The reversal of 18444971 is 17944481.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 18444971 - 2² = 18444967 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18444941) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10775 + ... + 12368.

It is an arithmetic number, because the mean of its divisors is an integer number (4617228).

Almost surely, 2^18444971 is an apocalyptic number.

18444971 is a deficient number, since it is larger than the sum of its proper divisors (23941).

18444971 is an equidigital number, since it uses as much as digits as its factorization.

18444971 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23940.

The product of its digits is 32256, while the sum is 38.

The square root of 18444971 is about 4294.7608780932. The cubic root of 18444971 is about 264.2161290661.

The spelling of 18444971 in words is "eighteen million, four hundred forty-four thousand, nine hundred seventy-one".