16556665443 has 4 divisors (see below), whose sum is σ = 22075553928. Its totient is φ = 11037776960.

The previous prime is 16556665399. The next prime is 16556665453. The reversal of 16556665443 is 34456665561.

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 16556665443 - 2²¹ = 16554568291 is a prime.

It is not an unprimeable number, because it can be changed into a prime (16556665453) 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, 2759444238 + ... + 2759444243.

It is an arithmetic number, because the mean of its divisors is an integer number (5518888482).

Almost surely, 2^16556665443 is an apocalyptic number.

16556665443 is a deficient number, since it is larger than the sum of its proper divisors (5518888485).

16556665443 is an equidigital number, since it uses as much as digits as its factorization.

16556665443 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5518888484.

The product of its digits is 7776000, while the sum is 51.

The spelling of 16556665443 in words is "sixteen billion, five hundred fifty-six million, six hundred sixty-five thousand, four hundred forty-three".