1681871 has 2 divisors, whose sum is σ = 1681872. Its totient is φ = 1681870.

The previous prime is 1681853. The next prime is 1681873. The reversal of 1681871 is 1781861.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1681871 - 2⁶ = 1681807 is a prime.

Together with 1681873, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1681873) 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, 840935 + 840936.

It is an arithmetic number, because the mean of its divisors is an integer number (840936).

2^1681871 is an apocalyptic number.

1681871 is a deficient number, since it is larger than the sum of its proper divisors (1).

1681871 is an equidigital number, since it uses as much as digits as its factorization.

1681871 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2688, while the sum is 32.

The square root of 1681871 is about 1296.8696927602. The cubic root of 1681871 is about 118.9225539443.

It can be divided in two parts, 1681 and 871, that added together give a palindrome (2552).

The spelling of 1681871 in words is "one million, six hundred eighty-one thousand, eight hundred seventy-one".