1668635464957 has 2 divisors, whose sum is σ = 1668635464958. Its totient is φ = 1668635464956.

The previous prime is 1668635464949. The next prime is 1668635464963. The reversal of 1668635464957 is 7594645368661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1654179250201 + 14456214756 = 1286149^2 + 120234^2 .

It is a cyclic number.

It is not a de Polignac number, because 1668635464957 - 2³ = 1668635464949 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1668635464907) 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, 834317732478 + 834317732479.

It is an arithmetic number, because the mean of its divisors is an integer number (834317732479).

Almost surely, 2^{1668635464957} is an apocalyptic number.

It is an amenable number.

1668635464957 is a deficient number, since it is larger than the sum of its proper divisors (1).

1668635464957 is an equidigital number, since it uses as much as digits as its factorization.

1668635464957 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 783820800, while the sum is 70.

The spelling of 1668635464957 in words is "one trillion, six hundred sixty-eight billion, six hundred thirty-five million, four hundred sixty-four thousand, nine hundred fifty-seven".