9876781 has 2 divisors, whose sum is σ = 9876782. Its totient is φ = 9876780.

The previous prime is 9876761. The next prime is 9876803. The reversal of 9876781 is 1876789.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 5428900 + 4447881 = 2330^2 + 2109^2 .

It is a cyclic number.

It is not a de Polignac number, because 9876781 - 2¹⁵ = 9844013 is a prime.

It is a super-2 number, since 2×9876781² = 195101605843922, which contains 22 as substring.

It is an Ulam number.

It is an alternating number because its digits alternate between odd and even.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (9876701) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4938390 + 4938391.

It is an arithmetic number, because the mean of its divisors is an integer number (4938391).

Almost surely, 2^9876781 is an apocalyptic number.

It is an amenable number.

9876781 is a deficient number, since it is larger than the sum of its proper divisors (1).

9876781 is an equidigital number, since it uses as much as digits as its factorization.

9876781 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 169344, while the sum is 46.

The square root of 9876781 is about 3142.7346372228. The cubic root of 9876781 is about 214.5549184440.

The spelling of 9876781 in words is "nine million, eight hundred seventy-six thousand, seven hundred eighty-one".