16656443643 has 16 divisors (see below), whose sum is σ = 26000303616. Its totient is φ = 9285821760.

The previous prime is 16656443611. The next prime is 16656443677. The reversal of 16656443643 is 34634465661.

It is a happy number.

It is not a de Polignac number, because 16656443643 - 2⁵ = 16656443611 is a prime.

It is a super-2 number, since 2×16656443643² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 16656443592 and 16656443601.

It is not an unprimeable number, because it can be changed into a prime (16656443603) 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 15 ways as a sum of consecutive naturals, for example, 9671871 + ... + 9673592.

It is an arithmetic number, because the mean of its divisors is an integer number (1625018976).

Almost surely, 2^16656443643 is an apocalyptic number.

16656443643 is a deficient number, since it is larger than the sum of its proper divisors (9343859973).

16656443643 is a wasteful number, since it uses less digits than its factorization.

16656443643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19345514.

The product of its digits is 3732480, while the sum is 48.

The spelling of 16656443643 in words is "sixteen billion, six hundred fifty-six million, four hundred forty-three thousand, six hundred forty-three".