1666850926817 has 2 divisors, whose sum is σ = 1666850926818. Its totient is φ = 1666850926816.

The previous prime is 1666850926787. The next prime is 1666850926877. The reversal of 1666850926817 is 7186290586661.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1597028677696 + 69822249121 = 1263736^2 + 264239^2 .

It is a cyclic number.

It is not a de Polignac number, because 1666850926817 - 2⁶ = 1666850926753 is a prime.

It is not a weakly prime, because it can be changed into another prime (1666850926877) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 833425463408 + 833425463409.

It is an arithmetic number, because the mean of its divisors is an integer number (833425463409).

Almost surely, 2^{1666850926817} is an apocalyptic number.

It is an amenable number.

1666850926817 is a deficient number, since it is larger than the sum of its proper divisors (1).

1666850926817 is an equidigital number, since it uses as much as digits as its factorization.

1666850926817 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 52254720, while the sum is 65.

The spelling of 1666850926817 in words is "one trillion, six hundred sixty-six billion, eight hundred fifty million, nine hundred twenty-six thousand, eight hundred seventeen".