1668888388513 has 2 divisors, whose sum is σ = 1668888388514. Its totient is φ = 1668888388512.

The previous prime is 1668888388499. The next prime is 1668888388547. The reversal of 1668888388513 is 3158838888661.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1310528117089 + 358360271424 = 1144783^2 + 598632^2 .

It is a cyclic number.

It is not a de Polignac number, because 1668888388513 - 2¹³ = 1668888380321 is a prime.

It is not a weakly prime, because it can be changed into another prime (1668888388313) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 834444194256 + 834444194257.

It is an arithmetic number, because the mean of its divisors is an integer number (834444194257).

Almost surely, 2^{1668888388513} is an apocalyptic number.

It is an amenable number.

1668888388513 is a deficient number, since it is larger than the sum of its proper divisors (1).

1668888388513 is an equidigital number, since it uses as much as digits as its factorization.

1668888388513 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 424673280, while the sum is 73.

The spelling of 1668888388513 in words is "one trillion, six hundred sixty-eight billion, eight hundred eighty-eight million, three hundred eighty-eight thousand, five hundred thirteen".