9967781 has 2 divisors, whose sum is σ = 9967782. Its totient is φ = 9967780.

The previous prime is 9967777. The next prime is 9967801. The reversal of 9967781 is 1877699.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 6974881 + 2992900 = 2641^2 + 1730^2 .

It is a cyclic number.

It is not a de Polignac number, because 9967781 - 2² = 9967777 is a prime.

It is a super-2 number, since 2×9967781² = 198713316127922, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (9967721) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4983890 + 4983891.

It is an arithmetic number, because the mean of its divisors is an integer number (4983891).

Almost surely, 2^9967781 is an apocalyptic number.

It is an amenable number.

9967781 is a deficient number, since it is larger than the sum of its proper divisors (1).

9967781 is an equidigital number, since it uses as much as digits as its factorization.

9967781 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 190512, while the sum is 47.

The square root of 9967781 is about 3157.1792790401. The cubic root of 9967781 is about 215.2118409597.

The spelling of 9967781 in words is "nine million, nine hundred sixty-seven thousand, seven hundred eighty-one".