6443645 has 8 divisors (see below), whose sum is σ = 8327256. Its totient is φ = 4758336.

The previous prime is 6443639. The next prime is 6443677. The reversal of 6443645 is 5463446.

It can be written as a sum of positive squares in 4 ways, for example, as 27556 + 6416089 = 166^2 + 2533^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 6443645 - 2⁸ = 6443389 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 49502 + ... + 49631.

It is an arithmetic number, because the mean of its divisors is an integer number (1040907).

Almost surely, 2^6443645 is an apocalyptic number.

6443645 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

It is an amenable number.

6443645 is a deficient number, since it is larger than the sum of its proper divisors (1883611).

6443645 is a wasteful number, since it uses less digits than its factorization.

6443645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 99151.

The product of its digits is 34560, while the sum is 32.

The square root of 6443645 is about 2538.4335721070. The cubic root of 6443645 is about 186.0846437119.

The spelling of 6443645 in words is "six million, four hundred forty-three thousand, six hundred forty-five".