1665510661056 has 56 divisors (see below), whose sum is σ = 4807269414144. Its totient is φ = 504700199680.

The previous prime is 1665510660953. The next prime is 1665510661057. The reversal of 1665510661056 is 6501660155661.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a junction number, because it is equal to n+sod(n) for n = 1665510660996 and 1665510661014.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1665510661057) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 394294920 + ... + 394299143.

Almost surely, 2^{1665510661056} is an apocalyptic number.

1665510661056 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

1665510661056 is an abundant number, since it is smaller than the sum of its proper divisors (3141758753088).

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

1665510661056 is a wasteful number, since it uses less digits than its factorization.

1665510661056 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 788594089 (or 788594079 counting only the distinct ones).

The product of its (nonzero) digits is 972000, while the sum is 48.

The spelling of 1665510661056 in words is "one trillion, six hundred sixty-five billion, five hundred ten million, six hundred sixty-one thousand, fifty-six".