1666320212 has 48 divisors (see below), whose sum is σ = 3156430032. Its totient is φ = 766771200.

The previous prime is 1666320203. The next prime is 1666320233. The reversal of 1666320212 is 2120236661.

It can be written as a sum of positive squares in 8 ways, for example, as 790396996 + 875923216 = 28114^2 + 29596^2 .

It is a congruent number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 1444628 + ... + 1445780.

It is an arithmetic number, because the mean of its divisors is an integer number (65758959).

Almost surely, 2^1666320212 is an apocalyptic number.

It is an amenable number.

1666320212 is a deficient number, since it is larger than the sum of its proper divisors (1490109820).

1666320212 is a wasteful number, since it uses less digits than its factorization.

1666320212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1628 (or 1626 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 29.

The square root of 1666320212 is about 40820.5856400910. The cubic root of 1666320212 is about 1185.5489423179.

Adding to 1666320212 its reverse (2120236661), we get a palindrome (3786556873).

The spelling of 1666320212 in words is "one billion, six hundred sixty-six million, three hundred twenty thousand, two hundred twelve".