218891941 has 2 divisors, whose sum is σ = 218891942. Its totient is φ = 218891940.

The previous prime is 218891929. The next prime is 218891969. The reversal of 218891941 is 149198812.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 193349025 + 25542916 = 13905^2 + 5054^2 .

It is a cyclic number.

It is not a de Polignac number, because 218891941 - 2⁹ = 218891429 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (218891041) 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, 109445970 + 109445971.

It is an arithmetic number, because the mean of its divisors is an integer number (109445971).

Almost surely, 2^218891941 is an apocalyptic number.

It is an amenable number.

218891941 is a deficient number, since it is larger than the sum of its proper divisors (1).

218891941 is an equidigital number, since it uses as much as digits as its factorization.

218891941 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 41472, while the sum is 43.

The square root of 218891941 is about 14794.9971612028. The cubic root of 218891941 is about 602.6658609151.

The spelling of 218891941 in words is "two hundred eighteen million, eight hundred ninety-one thousand, nine hundred forty-one".