208131894607729 has 9 divisors (see below), whose sum is σ = 208658020869921. Its totient is φ = 207607091740800.

The previous prime is 208131894607717. The next prime is 208131894607733. The reversal of 208131894607729 is 927706498131802.

The square root of 208131894607729 is 14426777.

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 193449571218225 + 14682323389504 = 13908615^2 + 3831752^2 .

It is not a de Polignac number, because 208131894607729 - 2⁵ = 208131894607697 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (208131894607129) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (31) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 5785119589 + ... + 5785155565.

Almost surely, 2^{208131894607729} is an apocalyptic number.

208131894607729 is the 14426777-th square number.

208131894607729 is the 7213389-th centered octagonal number.

It is an amenable number.

208131894607729 is a deficient number, since it is larger than the sum of its proper divisors (526126262192).

208131894607729 is an frugal number, since it uses more digits than its factorization.

208131894607729 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 72756 (or 36378 counting only the distinct ones).

The product of its (nonzero) digits is 73156608, while the sum is 67.

The spelling of 208131894607729 in words is "two hundred eight trillion, one hundred thirty-one billion, eight hundred ninety-four million, six hundred seven thousand, seven hundred twenty-nine".