9721124857 has 2 divisors, whose sum is σ = 9721124858. Its totient is φ = 9721124856.

The previous prime is 9721124839. The next prime is 9721124893. The reversal of 9721124857 is 7584211279.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 8395873641 + 1325251216 = 91629^2 + 36404^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-9721124857 is a prime.

It is not a weakly prime, because it can be changed into another prime (9721124837) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4860562428 + 4860562429.

It is an arithmetic number, because the mean of its divisors is an integer number (4860562429).

Almost surely, 2^9721124857 is an apocalyptic number.

It is an amenable number.

9721124857 is a deficient number, since it is larger than the sum of its proper divisors (1).

9721124857 is an equidigital number, since it uses as much as digits as its factorization.

9721124857 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 282240, while the sum is 46.

The square root of 9721124857 is about 98595.7649039755. The cubic root of 9721124857 is about 2134.2183045459.

The spelling of 9721124857 in words is "nine billion, seven hundred twenty-one million, one hundred twenty-four thousand, eight hundred fifty-seven".