1666031 has 4 divisors (see below), whose sum is σ = 1687200. Its totient is φ = 1644864.

The previous prime is 1666019. The next prime is 1666037. The reversal of 1666031 is 1306661.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1666031 - 2⁶ = 1665967 is a prime.

It is a super-3 number, since 3×1666031³ = 13873003282533323373, which contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1665988 and 1666006.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1666037) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10466 + ... + 10623.

It is an arithmetic number, because the mean of its divisors is an integer number (421800).

2^1666031 is an apocalyptic number.

1666031 is a deficient number, since it is larger than the sum of its proper divisors (21169).

1666031 is an equidigital number, since it uses as much as digits as its factorization.

1666031 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21168.

The product of its (nonzero) digits is 648, while the sum is 23.

The square root of 1666031 is about 1290.7482326155. The cubic root of 1666031 is about 118.5480349095.

The spelling of 1666031 in words is "one million, six hundred sixty-six thousand, thirty-one".