217040137 has 2 divisors, whose sum is σ = 217040138. Its totient is φ = 217040136.

The previous prime is 217040129. The next prime is 217040189. The reversal of 217040137 is 731040712.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 172029456 + 45010681 = 13116^2 + 6709^2 .

It is a cyclic number.

It is not a de Polignac number, because 217040137 - 2³ = 217040129 is a prime.

It is not a weakly prime, because it can be changed into another prime (217040237) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108520068 + 108520069.

It is an arithmetic number, because the mean of its divisors is an integer number (108520069).

Almost surely, 2^217040137 is an apocalyptic number.

It is an amenable number.

217040137 is a deficient number, since it is larger than the sum of its proper divisors (1).

217040137 is an equidigital number, since it uses as much as digits as its factorization.

217040137 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1176, while the sum is 25.

The square root of 217040137 is about 14732.2821382161. The cubic root of 217040137 is about 600.9615480339.

Adding to 217040137 its reverse (731040712), we get a palindrome (948080849).

The spelling of 217040137 in words is "two hundred seventeen million, forty thousand, one hundred thirty-seven".