1678361 has 2 divisors, whose sum is σ = 1678362. Its totient is φ = 1678360.

The previous prime is 1678349. The next prime is 1678363. The reversal of 1678361 is 1638761.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1038361 + 640000 = 1019^2 + 800^2 .

It is a cyclic number.

It is not a de Polignac number, because 1678361 - 2¹⁰ = 1677337 is a prime.

It is a Sophie Germain prime.

Together with 1678363, it forms a pair of twin primes.

It is a Chen prime.

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

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (1678363) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 839180 + 839181.

It is an arithmetic number, because the mean of its divisors is an integer number (839181).

2^1678361 is an apocalyptic number.

It is an amenable number.

1678361 is a deficient number, since it is larger than the sum of its proper divisors (1).

1678361 is an equidigital number, since it uses as much as digits as its factorization.

1678361 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6048, while the sum is 32.

The square root of 1678361 is about 1295.5157274229. The cubic root of 1678361 is about 118.8397673969.

The spelling of 1678361 in words is "one million, six hundred seventy-eight thousand, three hundred sixty-one".