218851247 has 2 divisors, whose sum is σ = 218851248. Its totient is φ = 218851246.

The previous prime is 218851159. The next prime is 218851301. The reversal of 218851247 is 742158812.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 218851247 - 2¹⁰ = 218850223 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 218851247.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (218851147) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 109425623 + 109425624.

It is an arithmetic number, because the mean of its divisors is an integer number (109425624).

Almost surely, 2^218851247 is an apocalyptic number.

218851247 is a deficient number, since it is larger than the sum of its proper divisors (1).

218851247 is an equidigital number, since it uses as much as digits as its factorization.

218851247 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 35840, while the sum is 38.

The square root of 218851247 is about 14793.6218351018. The cubic root of 218851247 is about 602.6285115813.

It can be divided in two parts, 21885 and 1247, that added together give a palindrome (23132).

The spelling of 218851247 in words is "two hundred eighteen million, eight hundred fifty-one thousand, two hundred forty-seven".