9871321 has 2 divisors, whose sum is σ = 9871322. Its totient is φ = 9871320.

The previous prime is 9871307. The next prime is 9871327. The reversal of 9871321 is 1231789.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 6702921 + 3168400 = 2589^2 + 1780^2 .

It is a cyclic number.

It is not a de Polignac number, because 9871321 - 2⁵ = 9871289 is a prime.

It is equal to p₆₅₆₆₇₁ and since 9871321 and 656671 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (9871327) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4935660 + 4935661.

It is an arithmetic number, because the mean of its divisors is an integer number (4935661).

Almost surely, 2^9871321 is an apocalyptic number.

It is an amenable number.

9871321 is a deficient number, since it is larger than the sum of its proper divisors (1).

9871321 is an equidigital number, since it uses as much as digits as its factorization.

9871321 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3024, while the sum is 31.

The square root of 9871321 is about 3141.8658469133. The cubic root of 9871321 is about 214.5153750007.

The spelling of 9871321 in words is "nine million, eight hundred seventy-one thousand, three hundred twenty-one".