1666828871 has 2 divisors, whose sum is σ = 1666828872. Its totient is φ = 1666828870.

The previous prime is 1666828829. The next prime is 1666828897. The reversal of 1666828871 is 1788286661.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1666828871 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1666828811) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 833414435 + 833414436.

It is an arithmetic number, because the mean of its divisors is an integer number (833414436).

Almost surely, 2^1666828871 is an apocalyptic number.

1666828871 is a deficient number, since it is larger than the sum of its proper divisors (1).

1666828871 is an equidigital number, since it uses as much as digits as its factorization.

1666828871 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1548288, while the sum is 53.

The square root of 1666828871 is about 40826.8155873073. The cubic root of 1666828871 is about 1185.6695631495.

The spelling of 1666828871 in words is "one billion, six hundred sixty-six million, eight hundred twenty-eight thousand, eight hundred seventy-one".