8378681 has 2 divisors, whose sum is σ = 8378682. Its totient is φ = 8378680.

The previous prime is 8378659. The next prime is 8378683. The reversal of 8378681 is 1868738.

8378681 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., 6250000 + 2128681 = 2500^2 + 1459^2 .

It is a cyclic number.

It is not a de Polignac number, because 8378681 - 2¹⁴ = 8362297 is a prime.

It is a super-2 number, since 2×8378681² = 140404590599522, which contains 22 as substring.

Together with 8378683, 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 (8378683) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4189340 + 4189341.

It is an arithmetic number, because the mean of its divisors is an integer number (4189341).

Almost surely, 2^8378681 is an apocalyptic number.

It is an amenable number.

8378681 is a deficient number, since it is larger than the sum of its proper divisors (1).

8378681 is an equidigital number, since it uses as much as digits as its factorization.

8378681 is an evil number, because the sum of its binary digits is even.

The product of its digits is 64512, while the sum is 41.

The square root of 8378681 is about 2894.5951357660. The cubic root of 8378681 is about 203.1071530197.

The spelling of 8378681 in words is "eight million, three hundred seventy-eight thousand, six hundred eighty-one".