19705702129 has 9 divisors (see below), whose sum is σ = 19824468993. Its totient is φ = 19587645072.

The previous prime is 19705702103. The next prime is 19705702139. The reversal of 19705702129 is 92120750791.

The square root of 19705702129 is 140377.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 840130225 + 18865571904 = 28985^2 + 137352^2 .

It is not a de Polignac number, because 19705702129 - 2⁵ = 19705702097 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19705702139) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 32146027 + ... + 32146639.

It is an arithmetic number, because the mean of its divisors is an integer number (2202718777).

Almost surely, 2^19705702129 is an apocalyptic number.

19705702129 is the 140377-th square number.

19705702129 is the 70189-th centered octagonal number.

It is an amenable number.

19705702129 is a deficient number, since it is larger than the sum of its proper divisors (118766864).

19705702129 is an frugal number, since it uses more digits than its factorization.

19705702129 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1684 (or 842 counting only the distinct ones).

The product of its (nonzero) digits is 79380, while the sum is 43.

The spelling of 19705702129 in words is "nineteen billion, seven hundred five million, seven hundred two thousand, one hundred twenty-nine".