1665653640043 has 4 divisors (see below), whose sum is σ = 1681220496600. Its totient is φ = 1650086783488.

The previous prime is 1665653640037. The next prime is 1665653640061. The reversal of 1665653640043 is 3400463565661.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1665653640043 - 2¹⁷ = 1665653508971 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1665653640143) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7783428118 + ... + 7783428331.

It is an arithmetic number, because the mean of its divisors is an integer number (420305124150).

Almost surely, 2^{1665653640043} is an apocalyptic number.

1665653640043 is a deficient number, since it is larger than the sum of its proper divisors (15566856557).

1665653640043 is a wasteful number, since it uses less digits than its factorization.

1665653640043 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15566856556.

The product of its (nonzero) digits is 4665600, while the sum is 49.

The spelling of 1665653640043 in words is "one trillion, six hundred sixty-five billion, six hundred fifty-three million, six hundred forty thousand, forty-three".