20718017 has 2 divisors, whose sum is σ = 20718018. Its totient is φ = 20718016.

The previous prime is 20718011. The next prime is 20718031. The reversal of 20718017 is 71081702.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20394256 + 323761 = 4516^2 + 569^2 .

It is a cyclic number.

It is not a de Polignac number, because 20718017 - 2⁶ = 20717953 is a prime.

It is not a weakly prime, because it can be changed into another prime (20718011) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10359008 + 10359009.

It is an arithmetic number, because the mean of its divisors is an integer number (10359009).

Almost surely, 2^20718017 is an apocalyptic number.

It is an amenable number.

20718017 is a deficient number, since it is larger than the sum of its proper divisors (1).

20718017 is an equidigital number, since it uses as much as digits as its factorization.

20718017 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 784, while the sum is 26.

The square root of 20718017 is about 4551.7048454398. The cubic root of 20718017 is about 274.6519762765.

Adding to 20718017 its reverse (71081702), we get a palindrome (91799719).

The spelling of 20718017 in words is "twenty million, seven hundred eighteen thousand, seventeen".