1666157047 has 2 divisors, whose sum is σ = 1666157048. Its totient is φ = 1666157046.

The previous prime is 1666157033. The next prime is 1666157081. The reversal of 1666157047 is 7407516661.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1666157047 - 2¹¹ = 1666154999 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1666156994 and 1666157012.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1666157347) 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 as a sum of consecutive naturals, namely, 833078523 + 833078524.

It is an arithmetic number, because the mean of its divisors is an integer number (833078524).

Almost surely, 2^1666157047 is an apocalyptic number.

1666157047 is a deficient number, since it is larger than the sum of its proper divisors (1).

1666157047 is an equidigital number, since it uses as much as digits as its factorization.

1666157047 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 211680, while the sum is 43.

The square root of 1666157047 is about 40818.5870284605. The cubic root of 1666157047 is about 1185.5102449923.

The spelling of 1666157047 in words is "one billion, six hundred sixty-six million, one hundred fifty-seven thousand, forty-seven".