1668502018361 has 2 divisors, whose sum is σ = 1668502018362. Its totient is φ = 1668502018360.

The previous prime is 1668502018297. The next prime is 1668502018369. The reversal of 1668502018361 is 1638102058661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1587814207225 + 80687811136 = 1260085^2 + 284056^2 .

It is a cyclic number.

It is not a de Polignac number, because 1668502018361 - 2⁶ = 1668502018297 is a prime.

It is a super-2 number, since 2×1668502018361² (a number of 25 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1668502018369) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 834251009180 + 834251009181.

It is an arithmetic number, because the mean of its divisors is an integer number (834251009181).

Almost surely, 2^{1668502018361} is an apocalyptic number.

It is an amenable number.

1668502018361 is a deficient number, since it is larger than the sum of its proper divisors (1).

1668502018361 is an equidigital number, since it uses as much as digits as its factorization.

1668502018361 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 414720, while the sum is 47.

The spelling of 1668502018361 in words is "one trillion, six hundred sixty-eight billion, five hundred two million, eighteen thousand, three hundred sixty-one".