1666867 has 8 divisors (see below), whose sum is σ = 1791072. Its totient is φ = 1545600.

The previous prime is 1666853. The next prime is 1666871. The reversal of 1666867 is 7686661.

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 1666867 - 2¹⁵ = 1634099 is a prime.

It is an Ulam number.

It is a Duffinian number.

1666867 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (1666807) 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 7 ways as a sum of consecutive naturals, for example, 517 + ... + 1897.

It is an arithmetic number, because the mean of its divisors is an integer number (223884).

2^1666867 is an apocalyptic number.

1666867 is a gapful number since it is divisible by the number (17) formed by its first and last digit.

1666867 is a deficient number, since it is larger than the sum of its proper divisors (124205).

1666867 is a wasteful number, since it uses less digits than its factorization.

1666867 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1469.

The product of its digits is 72576, while the sum is 40.

The square root of 1666867 is about 1291.0720351708. The cubic root of 1666867 is about 118.5678603880.

The spelling of 1666867 in words is "one million, six hundred sixty-six thousand, eight hundred sixty-seven".