18668203357 has 2 divisors, whose sum is σ = 18668203358. Its totient is φ = 18668203356.

The previous prime is 18668203291. The next prime is 18668203427. The reversal of 18668203357 is 75330286681.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18655735396 + 12467961 = 136586^2 + 3531^2 .

It is a cyclic number.

It is not a de Polignac number, because 18668203357 - 2²⁷ = 18533985629 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 18668203357.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18668203457) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9334101678 + 9334101679.

It is an arithmetic number, because the mean of its divisors is an integer number (9334101679).

Almost surely, 2^18668203357 is an apocalyptic number.

It is an amenable number.

18668203357 is a deficient number, since it is larger than the sum of its proper divisors (1).

18668203357 is an equidigital number, since it uses as much as digits as its factorization.

18668203357 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1451520, while the sum is 49.

The spelling of 18668203357 in words is "eighteen billion, six hundred sixty-eight million, two hundred three thousand, three hundred fifty-seven".