1660381784057 has 2 divisors, whose sum is σ = 1660381784058. Its totient is φ = 1660381784056.

The previous prime is 1660381784051. The next prime is 1660381784071. The reversal of 1660381784057 is 7504871830661.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1629939909481 + 30441874576 = 1276691^2 + 174476^2 .

It is an emirp because it is prime and its reverse (7504871830661) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1660381784057 - 2²² = 1660377589753 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1660381783993 and 1660381784011.

It is not a weakly prime, because it can be changed into another prime (1660381784051) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 830190892028 + 830190892029.

It is an arithmetic number, because the mean of its divisors is an integer number (830190892029).

Almost surely, 2^{1660381784057} is an apocalyptic number.

It is an amenable number.

1660381784057 is a deficient number, since it is larger than the sum of its proper divisors (1).

1660381784057 is an equidigital number, since it uses as much as digits as its factorization.

1660381784057 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6773760, while the sum is 56.

The spelling of 1660381784057 in words is "one trillion, six hundred sixty billion, three hundred eighty-one million, seven hundred eighty-four thousand, fifty-seven".