1681873 has 2 divisors, whose sum is σ = 1681874. Its totient is φ = 1681872.

The previous prime is 1681871. The next prime is 1681877. The reversal of 1681873 is 3781861.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1507984 + 173889 = 1228^2 + 417^2 .

It is a cyclic number.

It is not a de Polignac number, because 1681873 - 2¹ = 1681871 is a prime.

Together with 1681871, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (1681871) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 840936 + 840937.

It is an arithmetic number, because the mean of its divisors is an integer number (840937).

2^1681873 is an apocalyptic number.

It is an amenable number.

1681873 is a deficient number, since it is larger than the sum of its proper divisors (1).

1681873 is an equidigital number, since it uses as much as digits as its factorization.

1681873 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 8064, while the sum is 34.

The square root of 1681873 is about 1296.8704638475. The cubic root of 1681873 is about 118.9226010833.

The spelling of 1681873 in words is "one million, six hundred eighty-one thousand, eight hundred seventy-three".