16643561613 has 32 divisors (see below), whose sum is σ = 26763939840. Its totient is φ = 8987267520.

The previous prime is 16643561603. The next prime is 16643561657. The reversal of 16643561613 is 31616534661.

It is not a de Polignac number, because 16643561613 - 2⁶ = 16643561549 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16643561603) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 105868 + ... + 210938.

It is an arithmetic number, because the mean of its divisors is an integer number (836373120).

Almost surely, 2^16643561613 is an apocalyptic number.

It is an amenable number.

16643561613 is a deficient number, since it is larger than the sum of its proper divisors (10120378227).

16643561613 is a wasteful number, since it uses less digits than its factorization.

16643561613 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 105497.

The product of its digits is 233280, while the sum is 42.

The spelling of 16643561613 in words is "sixteen billion, six hundred forty-three million, five hundred sixty-one thousand, six hundred thirteen".