129720864061 has 2 divisors, whose sum is σ = 129720864062. Its totient is φ = 129720864060.

The previous prime is 129720863981. The next prime is 129720864109. The reversal of 129720864061 is 160468027921.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 113118541561 + 16602322500 = 336331^2 + 128850^2 .

It is a cyclic number.

It is not a de Polignac number, because 129720864061 - 2¹⁵ = 129720831293 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (129720864761) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64860432030 + 64860432031.

It is an arithmetic number, because the mean of its divisors is an integer number (64860432031).

Almost surely, 2^129720864061 is an apocalyptic number.

It is an amenable number.

129720864061 is a deficient number, since it is larger than the sum of its proper divisors (1).

129720864061 is an equidigital number, since it uses as much as digits as its factorization.

129720864061 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 290304, while the sum is 46.

The spelling of 129720864061 in words is "one hundred twenty-nine billion, seven hundred twenty million, eight hundred sixty-four thousand, sixty-one".