18947413 has 4 divisors (see below), whose sum is σ = 18970380. Its totient is φ = 18924448.

The previous prime is 18947363. The next prime is 18947419. The reversal of 18947413 is 31474981.

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 10227204 + 8720209 = 3198^2 + 2953^2 .

It is a cyclic number.

It is not a de Polignac number, because 18947413 - 2⁹ = 18946901 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 (18947419) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10198 + ... + 11911.

It is an arithmetic number, because the mean of its divisors is an integer number (4742595).

Almost surely, 2^18947413 is an apocalyptic number.

It is an amenable number.

18947413 is a deficient number, since it is larger than the sum of its proper divisors (22967).

18947413 is an equidigital number, since it uses as much as digits as its factorization.

18947413 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22966.

The product of its digits is 24192, while the sum is 37.

The square root of 18947413 is about 4352.8626213103. The cubic root of 18947413 is about 266.5937562824.

The spelling of 18947413 in words is "eighteen million, nine hundred forty-seven thousand, four hundred thirteen".