1666839629461 has 2 divisors, whose sum is σ = 1666839629462. Its totient is φ = 1666839629460.

The previous prime is 1666839629407. The next prime is 1666839629471. The reversal of 1666839629461 is 1649269386661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1205975152561 + 460864476900 = 1098169^2 + 678870^2 .

It is a cyclic number.

It is not a de Polignac number, because 1666839629461 - 2⁷ = 1666839629333 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1666839629471) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 833419814730 + 833419814731.

It is an arithmetic number, because the mean of its divisors is an integer number (833419814731).

Almost surely, 2^{1666839629461} is an apocalyptic number.

It is an amenable number.

1666839629461 is a deficient number, since it is larger than the sum of its proper divisors (1).

1666839629461 is an equidigital number, since it uses as much as digits as its factorization.

1666839629461 is an evil number, because the sum of its binary digits is even.

The product of its digits is 120932352, while the sum is 67.

The spelling of 1666839629461 in words is "one trillion, six hundred sixty-six billion, eight hundred thirty-nine million, six hundred twenty-nine thousand, four hundred sixty-one".