1666856 has 16 divisors (see below), whose sum is σ = 3261600. Its totient is φ = 797104.

The previous prime is 1666853. The next prime is 1666871. The reversal of 1666856 is 6586661.

It is not an unprimeable number, because it can be changed into a prime (1666853) 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 in 3 ways as a sum of consecutive naturals, for example, 4346 + ... + 4713.

It is an arithmetic number, because the mean of its divisors is an integer number (203850).

2^1666856 is an apocalyptic number.

It is an amenable number.

1666856 is a deficient number, since it is larger than the sum of its proper divisors (1594744).

1666856 is a wasteful number, since it uses less digits than its factorization.

1666856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9088 (or 9084 counting only the distinct ones).

The product of its digits is 51840, while the sum is 38.

The square root of 1666856 is about 1291.0677751381. The cubic root of 1666856 is about 118.5675995694.

The spelling of 1666856 in words is "one million, six hundred sixty-six thousand, eight hundred fifty-six".