218593091 has 2 divisors, whose sum is σ = 218593092. Its totient is φ = 218593090.

The previous prime is 218593057. The next prime is 218593093. The reversal of 218593091 is 190395812.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 218593091 - 2²² = 214398787 is a prime.

Together with 218593093, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (218593093) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 109296545 + 109296546.

It is an arithmetic number, because the mean of its divisors is an integer number (109296546).

Almost surely, 2^218593091 is an apocalyptic number.

218593091 is a deficient number, since it is larger than the sum of its proper divisors (1).

218593091 is an equidigital number, since it uses as much as digits as its factorization.

218593091 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 19440, while the sum is 38.

The square root of 218593091 is about 14784.8940138237. The cubic root of 218593091 is about 602.3914656745.

The spelling of 218593091 in words is "two hundred eighteen million, five hundred ninety-three thousand, ninety-one".