129515043817 has 2 divisors, whose sum is σ = 129515043818. Its totient is φ = 129515043816.

The previous prime is 129515043743. The next prime is 129515043821. The reversal of 129515043817 is 718340515921.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 118291972096 + 11223071721 = 343936^2 + 105939^2 .

It is a cyclic number.

It is not a de Polignac number, because 129515043817 - 2¹⁵ = 129515011049 is a prime.

It is not a weakly prime, because it can be changed into another prime (129515047817) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64757521908 + 64757521909.

It is an arithmetic number, because the mean of its divisors is an integer number (64757521909).

Almost surely, 2^129515043817 is an apocalyptic number.

It is an amenable number.

129515043817 is a deficient number, since it is larger than the sum of its proper divisors (1).

129515043817 is an equidigital number, since it uses as much as digits as its factorization.

129515043817 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 302400, while the sum is 46.

The spelling of 129515043817 in words is "one hundred twenty-nine billion, five hundred fifteen million, forty-three thousand, eight hundred seventeen".