1665171144945 has 96 divisors (see below), whose sum is σ = 3602857190400. Its totient is φ = 691181205120.

The previous prime is 1665171144941. The next prime is 1665171144947. The reversal of 1665171144945 is 5494411715661.

1665171144945 is a `hidden beast` number, since 1 + 6 + 6 + 517 + 114 + 4 + 9 + 4 + 5 = 666.

It is not a de Polignac number, because 1665171144945 - 2² = 1665171144941 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1665171144891 and 1665171144900.

It is not an unprimeable number, because it can be changed into a prime (1665171144941) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 2575006 + ... + 3156104.

It is an arithmetic number, because the mean of its divisors is an integer number (37529762400).

Almost surely, 2^{1665171144945} is an apocalyptic number.

1665171144945 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1665171144945 is an abundant number, since it is smaller than the sum of its proper divisors (1937686045455).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1665171144945 is a wasteful number, since it uses less digits than its factorization.

1665171144945 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 581955 (or 581952 counting only the distinct ones).

The product of its digits is 3628800, while the sum is 54.

The spelling of 1665171144945 in words is "one trillion, six hundred sixty-five billion, one hundred seventy-one million, one hundred forty-four thousand, nine hundred forty-five".