18847013 has 4 divisors (see below), whose sum is σ = 19496940. Its totient is φ = 18197088.

The previous prime is 18847009. The next prime is 18847027. The reversal of 18847013 is 31074881.

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

It can be written as a sum of positive squares in 2 ways, for example, as 15225604 + 3621409 = 3902^2 + 1903^2 .

It is a cyclic number.

It is not a de Polignac number, because 18847013 - 2² = 18847009 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 (18847313) 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, 324920 + ... + 324977.

It is an arithmetic number, because the mean of its divisors is an integer number (4874235).

Almost surely, 2^18847013 is an apocalyptic number.

It is an amenable number.

18847013 is a deficient number, since it is larger than the sum of its proper divisors (649927).

18847013 is an equidigital number, since it uses as much as digits as its factorization.

18847013 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 649926.

The product of its (nonzero) digits is 5376, while the sum is 32.

The square root of 18847013 is about 4341.3146626339. The cubic root of 18847013 is about 266.1220396528.

The spelling of 18847013 in words is "eighteen million, eight hundred forty-seven thousand, thirteen".