6443691005 has 6 divisors (see below), whose sum is σ = 7732644606. Its totient is φ = 5154809208.

The previous prime is 6443690993. The next prime is 6443691013. The reversal of 6443691005 is 5001963446.

It can be written as a sum of positive squares in only one way, i.e., 5154952804 + 1288738201 = 71798^2 + 35899^2 .

It is not a de Polignac number, because 6443691005 - 2⁶ = 6443690941 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 6443691005.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 161546 + ... + 197444.

It is an arithmetic number, because the mean of its divisors is an integer number (1288774101).

Almost surely, 2^6443691005 is an apocalyptic number.

It is an amenable number.

6443691005 is a deficient number, since it is larger than the sum of its proper divisors (1288953601).

6443691005 is an frugal number, since it uses more digits than its factorization.

6443691005 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71803 (or 35904 counting only the distinct ones).

The product of its (nonzero) digits is 77760, while the sum is 38.

The square root of 6443691005 is about 80272.6043242650. The cubic root of 6443691005 is about 1860.8508656702.

The spelling of 6443691005 in words is "six billion, four hundred forty-three million, six hundred ninety-one thousand, five".