1665666734403 has 32 divisors (see below), whose sum is σ = 2540918730240. Its totient is φ = 950775022080.

The previous prime is 1665666734393. The next prime is 1665666734437. The reversal of 1665666734403 is 3044376665661.

It is not a de Polignac number, because 1665666734403 - 2¹² = 1665666730307 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1665666734003) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 201430953 + ... + 201439221.

It is an arithmetic number, because the mean of its divisors is an integer number (79403710320).

Almost surely, 2^{1665666734403} is an apocalyptic number.

1665666734403 is a deficient number, since it is larger than the sum of its proper divisors (875251995837).

1665666734403 is a wasteful number, since it uses less digits than its factorization.

1665666734403 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17547.

The product of its (nonzero) digits is 39191040, while the sum is 57.

The spelling of 1665666734403 in words is "one trillion, six hundred sixty-five billion, six hundred sixty-six million, seven hundred thirty-four thousand, four hundred three".