20172617 has 2 divisors, whose sum is σ = 20172618. Its totient is φ = 20172616.

The previous prime is 20172613. The next prime is 20172637. The reversal of 20172617 is 71627102.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18181696 + 1990921 = 4264^2 + 1411^2 .

It is a cyclic number.

It is not a de Polignac number, because 20172617 - 2² = 20172613 is a prime.

It is a Chen prime.

It is equal to p_1280906 and since 20172617 and 1280906 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (20172613) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10086308 + 10086309.

It is an arithmetic number, because the mean of its divisors is an integer number (10086309).

Almost surely, 2^20172617 is an apocalyptic number.

It is an amenable number.

20172617 is a deficient number, since it is larger than the sum of its proper divisors (1).

20172617 is an equidigital number, since it uses as much as digits as its factorization.

20172617 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1176, while the sum is 26.

The square root of 20172617 is about 4491.3936589883. The cubic root of 20172617 is about 272.2204500664.

Adding to 20172617 its reverse (71627102), we get a palindrome (91799719).

The spelling of 20172617 in words is "twenty million, one hundred seventy-two thousand, six hundred seventeen".