18144947 has 4 divisors (see below), whose sum is σ = 18156936. Its totient is φ = 18132960.

The previous prime is 18144901. The next prime is 18144949. The reversal of 18144947 is 74944181.

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 18144947 - 2⁶ = 18144883 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 18144947.

It is not an unprimeable number, because it can be changed into a prime (18144949) 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, 3329 + ... + 6882.

It is an arithmetic number, because the mean of its divisors is an integer number (4539234).

Almost surely, 2^18144947 is an apocalyptic number.

18144947 is a deficient number, since it is larger than the sum of its proper divisors (11989).

18144947 is a wasteful number, since it uses less digits than its factorization.

18144947 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11988.

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

The square root of 18144947 is about 4259.6886036423. The cubic root of 18144947 is about 262.7757199679.

It can be divided in two parts, 18144 and 947, that added together give a palindrome (19091).

The spelling of 18144947 in words is "eighteen million, one hundred forty-four thousand, nine hundred forty-seven".