1666071 has 12 divisors (see below), whose sum is σ = 2625480. Its totient is φ = 1009680.

The previous prime is 1666061. The next prime is 1666081. The reversal of 1666071 is 1706661.

It is an interprime number because it is at equal distance from previous prime (1666061) and next prime (1666081).

It is not a de Polignac number, because 1666071 - 2⁵ = 1666039 is a prime.

1666071 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1666061) 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 11 ways as a sum of consecutive naturals, for example, 8316 + ... + 8513.

It is an arithmetic number, because the mean of its divisors is an integer number (218790).

2^1666071 is an apocalyptic number.

1666071 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1666071 is a deficient number, since it is larger than the sum of its proper divisors (959409).

1666071 is a wasteful number, since it uses less digits than its factorization.

1666071 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16846 (or 16843 counting only the distinct ones).

The product of its (nonzero) digits is 1512, while the sum is 27.

The square root of 1666071 is about 1290.7637274110. The cubic root of 1666071 is about 118.5489836481.

The spelling of 1666071 in words is "one million, six hundred sixty-six thousand, seventy-one".