1681986 has 16 divisors (see below), whose sum is σ = 3383424. Its totient is φ = 557424.

The previous prime is 1681973. The next prime is 1681991. The reversal of 1681986 is 6891861.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 471 + ... + 1893.

It is an arithmetic number, because the mean of its divisors is an integer number (211464).

2^1681986 is an apocalyptic number.

1681986 is an abundant number, since it is smaller than the sum of its proper divisors (1701438).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1681986 is a wasteful number, since it uses less digits than its factorization.

1681986 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1625.

The product of its digits is 20736, while the sum is 39.

The square root of 1681986 is about 1296.9140295332. The cubic root of 1681986 is about 118.9252643746.

The spelling of 1681986 in words is "one million, six hundred eighty-one thousand, nine hundred eighty-six".