217061289 has 15 divisors (see below), whose sum is σ = 324450247. Its totient is φ = 144619128.

The previous prime is 217061267. The next prime is 217061309. The reversal of 217061289 is 982160712.

The square root of 217061289 is 14733.

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

217061289 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 6579225 + 210482064 = 2565^2 + 14508^2 .

It is not a de Polignac number, because 217061289 - 2¹⁹ = 216537001 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (217061239) by changing a digit.

It is a polite number, since it can be written in 14 ways as a sum of consecutive naturals, for example, 131779 + ... + 133415.

Almost surely, 2^217061289 is an apocalyptic number.

217061289 is the 14733-rd square number.

217061289 is the 7367-th centered octagonal number.

It is an amenable number.

217061289 is a deficient number, since it is larger than the sum of its proper divisors (107388958).

217061289 is an frugal number, since it uses more digits than its factorization.

217061289 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3286 (or 1640 counting only the distinct ones).

The product of its (nonzero) digits is 12096, while the sum is 36.

The cubic root of 217061289 is about 600.9810699619.

Multiplying 217061289 by its sum of digits (36), we get a square (7814206404 = 88398²).

The spelling of 217061289 in words is "two hundred seventeen million, sixty-one thousand, two hundred eighty-nine".