9729171661 has 8 divisors (see below), whose sum is σ = 10615354848. Its totient is φ = 8843274000.

The previous prime is 9729171611. The next prime is 9729171679. The reversal of 9729171661 is 1661719279.

9729171661 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 9729171661 - 2¹³ = 9729163469 is a prime.

It is a super-3 number, since 3×9729171661³ (a number of 31 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9729171601) 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 7 ways as a sum of consecutive naturals, for example, 3271 + ... + 139531.

It is an arithmetic number, because the mean of its divisors is an integer number (1326919356).

Almost surely, 2^9729171661 is an apocalyptic number.

It is an amenable number.

9729171661 is a deficient number, since it is larger than the sum of its proper divisors (886183187).

9729171661 is a wasteful number, since it uses less digits than its factorization.

9729171661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 142763.

The product of its digits is 285768, while the sum is 49.

The square root of 9729171661 is about 98636.5635096844. The cubic root of 9729171661 is about 2134.8070189949.

The spelling of 9729171661 in words is "nine billion, seven hundred twenty-nine million, one hundred seventy-one thousand, six hundred sixty-one".