1686881 has 8 divisors (see below), whose sum is σ = 1943040. Its totient is φ = 1434528.

The previous prime is 1686871. The next prime is 1686907. The reversal of 1686881 is 1886861.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1686881 - 2¹⁸ = 1424737 is a prime.

It is a super-2 number, since 2×1686881² = 5691135016322, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1686851) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 80 + ... + 1838.

It is an arithmetic number, because the mean of its divisors is an integer number (242880).

2^1686881 is an apocalyptic number.

It is an amenable number.

1686881 is a deficient number, since it is larger than the sum of its proper divisors (256159).

1686881 is a wasteful number, since it uses less digits than its factorization.

1686881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1903.

The product of its digits is 18432, while the sum is 38.

The square root of 1686881 is about 1298.7998306129. The cubic root of 1686881 is about 119.0405200618.

The spelling of 1686881 in words is "one million, six hundred eighty-six thousand, eight hundred eighty-one".