1666851833497 has 2 divisors, whose sum is σ = 1666851833498. Its totient is φ = 1666851833496.

The previous prime is 1666851833419. The next prime is 1666851833531. The reversal of 1666851833497 is 7943381586661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1017185205136 + 649666628361 = 1008556^2 + 806019^2 .

It is a cyclic number.

It is not a de Polignac number, because 1666851833497 - 2⁷ = 1666851833369 is a prime.

It is a super-2 number, since 2×1666851833497² (a number of 25 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1666851833417) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 833425916748 + 833425916749.

It is an arithmetic number, because the mean of its divisors is an integer number (833425916749).

Almost surely, 2^{1666851833497} is an apocalyptic number.

It is an amenable number.

1666851833497 is a deficient number, since it is larger than the sum of its proper divisors (1).

1666851833497 is an equidigital number, since it uses as much as digits as its factorization.

1666851833497 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 156764160, while the sum is 67.

The spelling of 1666851833497 in words is "one trillion, six hundred sixty-six billion, eight hundred fifty-one million, eight hundred thirty-three thousand, four hundred ninety-seven".