218641 has 2 divisors, whose sum is σ = 218642. Its totient is φ = 218640.

The previous prime is 218629. The next prime is 218651. The reversal of 218641 is 146812.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 115600 + 103041 = 340^2 + 321^2 .

It is a cyclic number.

It is not a de Polignac number, because 218641 - 2⁷ = 218513 is a prime.

It is a nialpdrome in base 12.

It is not a weakly prime, because it can be changed into another prime (218611) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 109320 + 109321.

It is an arithmetic number, because the mean of its divisors is an integer number (109321).

2²¹⁸⁶⁴¹ is an apocalyptic number.

It is an amenable number.

218641 is a deficient number, since it is larger than the sum of its proper divisors (1).

218641 is an equidigital number, since it uses as much as digits as its factorization.

218641 is an evil number, because the sum of its binary digits is even.

The product of its digits is 384, while the sum is 22.

The square root of 218641 is about 467.5906329259. The cubic root of 218641 is about 60.2435471128.

The spelling of 218641 in words is "two hundred eighteen thousand, six hundred forty-one".