1685978 has 8 divisors (see below), whose sum is σ = 2890272. Its totient is φ = 722556.

The previous prime is 1685977. The next prime is 1685989. The reversal of 1685978 is 8795861.

It is a happy number.

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

It is not an unprimeable number, because it can be changed into a prime (1685977) 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 in 3 ways as a sum of consecutive naturals, for example, 60200 + ... + 60227.

It is an arithmetic number, because the mean of its divisors is an integer number (361284).

2^1685978 is an apocalyptic number.

1685978 is a deficient number, since it is larger than the sum of its proper divisors (1204294).

1685978 is a wasteful number, since it uses less digits than its factorization.

1685978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 120436.

The product of its digits is 120960, while the sum is 44.

The square root of 1685978 is about 1298.4521554528. The cubic root of 1685978 is about 119.0192751773.

The spelling of 1685978 in words is "one million, six hundred eighty-five thousand, nine hundred seventy-eight".