218104878289 has 3 divisors (see below), whose sum is σ = 218105345307. Its totient is φ = 218104411272.

The previous prime is 218104878263. The next prime is 218104878293. The reversal of 218104878289 is 982878401812.

The square root of 218104878289 is 467017.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in only one way, i.e., 2615811025 + 215489067264 = 51145^2 + 464208^2 .

It is not a de Polignac number, because 218104878289 - 2¹⁵ = 218104845521 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (218104878389) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 233509 + ... + 700525.

It is an arithmetic number, because the mean of its divisors is an integer number (72701781769).

Almost surely, 2^218104878289 is an apocalyptic number.

218104878289 is the 467017-th square number.

218104878289 is the 233509-th centered octagonal number.

It is an amenable number.

218104878289 is a deficient number, since it is larger than the sum of its proper divisors (467018).

218104878289 is an frugal number, since it uses more digits than its factorization.

218104878289 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 934034 (or 467017 counting only the distinct ones).

The product of its (nonzero) digits is 4128768, while the sum is 58.

The spelling of 218104878289 in words is "two hundred eighteen billion, one hundred four million, eight hundred seventy-eight thousand, two hundred eighty-nine".