218942887 has 2 divisors, whose sum is σ = 218942888. Its totient is φ = 218942886.

The previous prime is 218942869. The next prime is 218942897. The reversal of 218942887 is 788249812.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-218942887 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 218942887.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (218942827) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 109471443 + 109471444.

It is an arithmetic number, because the mean of its divisors is an integer number (109471444).

Almost surely, 2^218942887 is an apocalyptic number.

218942887 is a deficient number, since it is larger than the sum of its proper divisors (1).

218942887 is an equidigital number, since it uses as much as digits as its factorization.

218942887 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 516096, while the sum is 49.

The square root of 218942887 is about 14796.7187916781. The cubic root of 218942887 is about 602.7126131057.

The spelling of 218942887 in words is "two hundred eighteen million, nine hundred forty-two thousand, eight hundred eighty-seven".