291217 has 2 divisors, whose sum is σ = 291218. Its totient is φ = 291216.

The previous prime is 291209. The next prime is 291253. The reversal of 291217 is 712192.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 274576 + 16641 = 524^2 + 129^2 .

It is a cyclic number.

It is not a de Polignac number, because 291217 - 2³ = 291209 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (291257) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 145608 + 145609.

It is an arithmetic number, because the mean of its divisors is an integer number (145609).

2²⁹¹²¹⁷ is an apocalyptic number.

It is an amenable number.

291217 is a deficient number, since it is larger than the sum of its proper divisors (1).

291217 is an equidigital number, since it uses as much as digits as its factorization.

291217 is an evil number, because the sum of its binary digits is even.

The product of its digits is 252, while the sum is 22.

The square root of 291217 is about 539.6452538474. The cubic root of 291217 is about 66.2835216614.

It can be divided in two parts, 2 and 91217, that added together give a palindrome (91219).

The spelling of 291217 in words is "two hundred ninety-one thousand, two hundred seventeen".