218443493 has 2 divisors, whose sum is σ = 218443494. Its totient is φ = 218443492.

The previous prime is 218443487. The next prime is 218443541. The reversal of 218443493 is 394344812.

218443493 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 166358404 + 52085089 = 12898^2 + 7217^2 .

It is a cyclic number.

It is not a de Polignac number, because 218443493 - 2⁸ = 218443237 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (218443403) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 109221746 + 109221747.

It is an arithmetic number, because the mean of its divisors is an integer number (109221747).

Almost surely, 2^218443493 is an apocalyptic number.

It is an amenable number.

218443493 is a deficient number, since it is larger than the sum of its proper divisors (1).

218443493 is an equidigital number, since it uses as much as digits as its factorization.

218443493 is an evil number, because the sum of its binary digits is even.

The product of its digits is 82944, while the sum is 38.

The square root of 218443493 is about 14779.8339977146. The cubic root of 218443493 is about 602.2540152737.

The spelling of 218443493 in words is "two hundred eighteen million, four hundred forty-three thousand, four hundred ninety-three".