218638087 has 2 divisors, whose sum is σ = 218638088. Its totient is φ = 218638086.

The previous prime is 218638067. The next prime is 218638099. The reversal of 218638087 is 780836812.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-218638087 is a prime.

It is a super-2 number, since 2×218638087² = 95605226174039138, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (218638027) 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 as a sum of consecutive naturals, namely, 109319043 + 109319044.

It is an arithmetic number, because the mean of its divisors is an integer number (109319044).

Almost surely, 2^218638087 is an apocalyptic number.

218638087 is a deficient number, since it is larger than the sum of its proper divisors (1).

218638087 is an equidigital number, since it uses as much as digits as its factorization.

218638087 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 129024, while the sum is 43.

The square root of 218638087 is about 14786.4156238082. The cubic root of 218638087 is about 602.4327956584.

The spelling of 218638087 in words is "two hundred eighteen million, six hundred thirty-eight thousand, eighty-seven".