9871649 has 2 divisors, whose sum is σ = 9871650. Its totient is φ = 9871648.

The previous prime is 9871633. The next prime is 9871651. The reversal of 9871649 is 9461789.

9871649 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 5607424 + 4264225 = 2368^2 + 2065^2 .

It is a cyclic number.

It is not a de Polignac number, because 9871649 - 2⁴ = 9871633 is a prime.

Together with 9871651, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (9871619) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4935824 + 4935825.

It is an arithmetic number, because the mean of its divisors is an integer number (4935825).

Almost surely, 2^9871649 is an apocalyptic number.

It is an amenable number.

9871649 is a deficient number, since it is larger than the sum of its proper divisors (1).

9871649 is an equidigital number, since it uses as much as digits as its factorization.

9871649 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 108864, while the sum is 44.

The square root of 9871649 is about 3141.9180447618. The cubic root of 9871649 is about 214.5177509159.

The spelling of 9871649 in words is "nine million, eight hundred seventy-one thousand, six hundred forty-nine".