18131413 has 2 divisors, whose sum is σ = 18131414. Its totient is φ = 18131412.

The previous prime is 18131411. The next prime is 18131417. The reversal of 18131413 is 31413181.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17791524 + 339889 = 4218^2 + 583^2 .

It is an emirp because it is prime and its reverse (31413181) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18131413 - 2¹ = 18131411 is a prime.

Together with 18131411, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18131411) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9065706 + 9065707.

It is an arithmetic number, because the mean of its divisors is an integer number (9065707).

Almost surely, 2^18131413 is an apocalyptic number.

It is an amenable number.

18131413 is a deficient number, since it is larger than the sum of its proper divisors (1).

18131413 is an equidigital number, since it uses as much as digits as its factorization.

18131413 is an evil number, because the sum of its binary digits is even.

The product of its digits is 288, while the sum is 22.

The square root of 18131413 is about 4258.0996935253. The cubic root of 18131413 is about 262.7103704396.

Adding to 18131413 its reverse (31413181), we get a palindrome (49544594).

The spelling of 18131413 in words is "eighteen million, one hundred thirty-one thousand, four hundred thirteen".