218228401 has 6 divisors (see below), whose sum is σ = 222426470. Its totient is φ = 214108128.

The previous prime is 218228383. The next prime is 218228407. The reversal of 218228401 is 104822812.

It can be written as a sum of positive squares in 3 ways, for example, as 95550625 + 122677776 = 9775^2 + 11076^2 .

It is not a de Polignac number, because 218228401 - 2¹¹ = 218226353 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 218228401.

It is not an unprimeable number, because it can be changed into a prime (218228407) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 36036 + ... + 41653.

Almost surely, 2^218228401 is an apocalyptic number.

It is an amenable number.

218228401 is a deficient number, since it is larger than the sum of its proper divisors (4198069).

218228401 is an frugal number, since it uses more digits than its factorization.

218228401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77795 (or 77742 counting only the distinct ones).

The product of its (nonzero) digits is 2048, while the sum is 28.

The square root of 218228401 is about 14772.5556692131. Note that the first 3 decimals coincide. The cubic root of 218228401 is about 602.0562790694.

The spelling of 218228401 in words is "two hundred eighteen million, two hundred twenty-eight thousand, four hundred one".