18218371 has 2 divisors, whose sum is σ = 18218372. Its totient is φ = 18218370.

The previous prime is 18218357. The next prime is 18218381. The reversal of 18218371 is 17381281.

It is a happy number.

It is a strong prime.

It is an emirp because it is prime and its reverse (17381281) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18218371 - 2¹¹ = 18216323 is a prime.

It is not a weakly prime, because it can be changed into another prime (18218311) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9109185 + 9109186.

It is an arithmetic number, because the mean of its divisors is an integer number (9109186).

Almost surely, 2^18218371 is an apocalyptic number.

18218371 is a deficient number, since it is larger than the sum of its proper divisors (1).

18218371 is an equidigital number, since it uses as much as digits as its factorization.

18218371 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2688, while the sum is 31.

The square root of 18218371 is about 4268.2983728882. The cubic root of 18218371 is about 263.1296858809.

The spelling of 18218371 in words is "eighteen million, two hundred eighteen thousand, three hundred seventy-one".