129780215723 has 2 divisors, whose sum is σ = 129780215724. Its totient is φ = 129780215722.

The previous prime is 129780215699. The next prime is 129780215819. The reversal of 129780215723 is 327512087921.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 129780215723 - 2³⁰ = 128706473899 is a prime.

It is not a weakly prime, because it can be changed into another prime (129780215623) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64890107861 + 64890107862.

It is an arithmetic number, because the mean of its divisors is an integer number (64890107862).

Almost surely, 2^129780215723 is an apocalyptic number.

129780215723 is a deficient number, since it is larger than the sum of its proper divisors (1).

129780215723 is an equidigital number, since it uses as much as digits as its factorization.

129780215723 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 423360, while the sum is 47.

The spelling of 129780215723 in words is "one hundred twenty-nine billion, seven hundred eighty million, two hundred fifteen thousand, seven hundred twenty-three".