9971729 has 2 divisors, whose sum is σ = 9971730. Its totient is φ = 9971728.

The previous prime is 9971711. The next prime is 9971749. The reversal of 9971729 is 9271799.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 9778129 + 193600 = 3127^2 + 440^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-9971729 is a prime.

It is an Ulam number.

It is a self number, because there is not a number n which added to its sum of digits gives 9971729.

It is not a weakly prime, because it can be changed into another prime (9971749) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4985864 + 4985865.

It is an arithmetic number, because the mean of its divisors is an integer number (4985865).

Almost surely, 2^9971729 is an apocalyptic number.

It is an amenable number.

9971729 is a deficient number, since it is larger than the sum of its proper divisors (1).

9971729 is an equidigital number, since it uses as much as digits as its factorization.

9971729 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 71442, while the sum is 44.

The square root of 9971729 is about 3157.8044587973. The cubic root of 9971729 is about 215.2402506327.

The spelling of 9971729 in words is "nine million, nine hundred seventy-one thousand, seven hundred twenty-nine".