9666643643 has 24 divisors (see below), whose sum is σ = 10252810704. Its totient is φ = 9106344000.

The previous prime is 9666643639. The next prime is 9666643733. The reversal of 9666643643 is 3463466669.

It is not a de Polignac number, because 9666643643 - 2² = 9666643639 is a prime.

It is a super-2 number, since 2×9666643643² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (9666643633) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 8254448 + ... + 8255618.

It is an arithmetic number, because the mean of its divisors is an integer number (427200446).

Almost surely, 2^9666643643 is an apocalyptic number.

9666643643 is a deficient number, since it is larger than the sum of its proper divisors (586167061).

9666643643 is a wasteful number, since it uses less digits than its factorization.

9666643643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1403 (or 1356 counting only the distinct ones).

The product of its digits is 10077696, while the sum is 53.

The square root of 9666643643 is about 98319.0909386371. The cubic root of 9666643643 is about 2130.2238182374.

The spelling of 9666643643 in words is "nine billion, six hundred sixty-six million, six hundred forty-three thousand, six hundred forty-three".