251117107122017 has 2 divisors, whose sum is σ = 251117107122018. Its totient is φ = 251117107122016.

The previous prime is 251117107121987. The next prime is 251117107122041. The reversal of 251117107122017 is 710221701711152.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 147943336934416 + 103173770187601 = 12163196^2 + 10157449^2 .

It is a cyclic number.

It is not a de Polignac number, because 251117107122017 - 2⁶ = 251117107121953 is a prime.

It is a super-2 number, since 2×251117107122017² (a number of 30 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (251117107122517) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 125558553561008 + 125558553561009.

It is an arithmetic number, because the mean of its divisors is an integer number (125558553561009).

Almost surely, 2^{251117107122017} is an apocalyptic number.

It is an amenable number.

251117107122017 is a deficient number, since it is larger than the sum of its proper divisors (1).

251117107122017 is an equidigital number, since it uses as much as digits as its factorization.

251117107122017 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 13720, while the sum is 38.

Adding to 251117107122017 its reverse (710221701711152), we get a palindrome (961338808833169).

The spelling of 251117107122017 in words is "two hundred fifty-one trillion, one hundred seventeen billion, one hundred seven million, one hundred twenty-two thousand, seventeen".