1381866 has 8 divisors (see below), whose sum is σ = 2763744. Its totient is φ = 460620.

The previous prime is 1381859. The next prime is 1381871. The reversal of 1381866 is 6681831.

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

1381866 is an admirable number.

It is an unprimeable number.

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, 115150 + ... + 115161.

It is an arithmetic number, because the mean of its divisors is an integer number (345468).

2^1381866 is an apocalyptic number.

1381866 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

1381866 is a wasteful number, since it uses less digits than its factorization.

1381866 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 230316.

The product of its digits is 6912, while the sum is 33.

The square root of 1381866 is about 1175.5279664900. The cubic root of 1381866 is about 111.3837863606.

The spelling of 1381866 in words is "one million, three hundred eighty-one thousand, eight hundred sixty-six".