1666071031 has 4 divisors (see below), whose sum is σ = 1753759000. Its totient is φ = 1578383064.

The previous prime is 1666071023. The next prime is 1666071049. The reversal of 1666071031 is 1301706661.

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 1666071031 - 2³ = 1666071023 is a prime.

It is a super-2 number, since 2×1666071031² = 5551585360674805922, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1666070984 and 1666071002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1666077031) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 43843956 + ... + 43843993.

It is an arithmetic number, because the mean of its divisors is an integer number (438439750).

Almost surely, 2^1666071031 is an apocalyptic number.

1666071031 is a deficient number, since it is larger than the sum of its proper divisors (87687969).

1666071031 is an equidigital number, since it uses as much as digits as its factorization.

1666071031 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 87687968.

The product of its (nonzero) digits is 4536, while the sum is 31.

The square root of 1666071031 is about 40817.5333772143. The cubic root of 1666071031 is about 1185.4898438334.

Adding to 1666071031 its reverse (1301706661), we get a palindrome (2967777692).

The spelling of 1666071031 in words is "one billion, six hundred sixty-six million, seventy-one thousand, thirty-one".