1666832213 has 2 divisors, whose sum is σ = 1666832214. Its totient is φ = 1666832212.

The previous prime is 1666832191. The next prime is 1666832221. The reversal of 1666832213 is 3122386661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1472870884 + 193961329 = 38378^2 + 13927^2 .

It is an emirp because it is prime and its reverse (3122386661) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1666832213 - 2³⁰ = 593090389 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1666832113) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 833416106 + 833416107.

It is an arithmetic number, because the mean of its divisors is an integer number (833416107).

Almost surely, 2^1666832213 is an apocalyptic number.

It is an amenable number.

1666832213 is a deficient number, since it is larger than the sum of its proper divisors (1).

1666832213 is an equidigital number, since it uses as much as digits as its factorization.

1666832213 is an evil number, because the sum of its binary digits is even.

The product of its digits is 62208, while the sum is 38.

The square root of 1666832213 is about 40826.8565162688. The cubic root of 1666832213 is about 1185.6703555734.

The spelling of 1666832213 in words is "one billion, six hundred sixty-six million, eight hundred thirty-two thousand, two hundred thirteen".