129865242257 has 2 divisors, whose sum is σ = 129865242258. Its totient is φ = 129865242256.

The previous prime is 129865242251. The next prime is 129865242343. The reversal of 129865242257 is 752242568921.

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., 128095273216 + 1769969041 = 357904^2 + 42071^2 .

It is an emirp because it is prime and its reverse (752242568921) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 129865242257 - 2²⁰ = 129864193681 is a prime.

It is a super-2 number, since 2×129865242257² (a number of 23 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 129865242199 and 129865242208.

It is not a weakly prime, because it can be changed into another prime (129865242251) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64932621128 + 64932621129.

It is an arithmetic number, because the mean of its divisors is an integer number (64932621129).

Almost surely, 2^129865242257 is an apocalyptic number.

It is an amenable number.

129865242257 is a deficient number, since it is larger than the sum of its proper divisors (1).

129865242257 is an equidigital number, since it uses as much as digits as its factorization.

129865242257 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4838400, while the sum is 53.

The spelling of 129865242257 in words is "one hundred twenty-nine billion, eight hundred sixty-five million, two hundred forty-two thousand, two hundred fifty-seven".