1666325161 has 2 divisors, whose sum is σ = 1666325162. Its totient is φ = 1666325160.

The previous prime is 1666325147. The next prime is 1666325173. The reversal of 1666325161 is 1615236661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1007427600 + 658897561 = 31740^2 + 25669^2 .

It is an emirp because it is prime and its reverse (1615236661) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1666325161 - 2¹³ = 1666316969 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1666325161.

It is not a weakly prime, because it can be changed into another prime (1666325191) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 833162580 + 833162581.

It is an arithmetic number, because the mean of its divisors is an integer number (833162581).

Almost surely, 2^1666325161 is an apocalyptic number.

It is an amenable number.

1666325161 is a deficient number, since it is larger than the sum of its proper divisors (1).

1666325161 is an equidigital number, since it uses as much as digits as its factorization.

1666325161 is an evil number, because the sum of its binary digits is even.

The product of its digits is 38880, while the sum is 37.

The square root of 1666325161 is about 40820.6462589705. The cubic root of 1666325161 is about 1185.5501160171.

The spelling of 1666325161 in words is "one billion, six hundred sixty-six million, three hundred twenty-five thousand, one hundred sixty-one".