1645105642117 has 12 divisors (see below), whose sum is σ = 1931251153260. Its totient is φ = 1397153935296.

The previous prime is 1645105642111. The next prime is 1645105642129. The reversal of 1645105642117 is 7112465015461.

It can be written as a sum of positive squares in 2 ways, for example, as 508267759041 + 1136837883076 = 712929^2 + 1066226^2 .

It is not a de Polignac number, because 1645105642117 - 2¹¹ = 1645105640069 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1645105642111) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 154001928 + ... + 154012609.

It is an arithmetic number, because the mean of its divisors is an integer number (160937596105).

Almost surely, 2^{1645105642117} is an apocalyptic number.

It is an amenable number.

1645105642117 is a deficient number, since it is larger than the sum of its proper divisors (286145511143).

1645105642117 is a wasteful number, since it uses less digits than its factorization.

1645105642117 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 308014660 (or 308014653 counting only the distinct ones).

The product of its (nonzero) digits is 201600, while the sum is 43.

The spelling of 1645105642117 in words is "one trillion, six hundred forty-five billion, one hundred five million, six hundred forty-two thousand, one hundred seventeen".