20100717729 has 63 divisors (see below), whose sum is σ = 31005077443. Its totient is φ = 13025336544.

The previous prime is 20100717701. The next prime is 20100717733. The reversal of 20100717729 is 92771700102.

The square root of 20100717729 is 141777.

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

It can be written as a sum of positive squares in only one way, i.e., 3859764129 + 16240953600 = 62127^2 + 127440^2 .

It is not a de Polignac number, because 20100717729 - 2¹⁹ = 20100193441 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20100717693 and 20100717702.

It is not an unprimeable number, because it can be changed into a prime (20100717799) by changing a digit.

It is a polite number, since it can be written in 62 ways as a sum of consecutive naturals, for example, 225850717 + ... + 225850805.

Almost surely, 2^20100717729 is an apocalyptic number.

20100717729 is the 141777-th square number.

20100717729 is the 70889-th centered octagonal number.

It is an amenable number.

20100717729 is a deficient number, since it is larger than the sum of its proper divisors (10904359714).

20100717729 is an frugal number, since it uses more digits than its factorization.

20100717729 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 314 (or 151 counting only the distinct ones).

The product of its (nonzero) digits is 12348, while the sum is 36.

Multiplying 20100717729 by its sum of digits (36), we get a square (723625838244 = 850662²).

The spelling of 20100717729 in words is "twenty billion, one hundred million, seven hundred seventeen thousand, seven hundred twenty-nine".