6642635443 has 16 divisors (see below), whose sum is σ = 6918557184. Its totient is φ = 6373049760.

The previous prime is 6642635431. The next prime is 6642635473. The reversal of 6642635443 is 3445362466.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 6642635443 - 2⁵ = 6642635411 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 6642635443.

It is not an unprimeable number, because it can be changed into a prime (6642635423) 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, 876396 + ... + 883942.

It is an arithmetic number, because the mean of its divisors is an integer number (432409824).

Almost surely, 2^6642635443 is an apocalyptic number.

6642635443 is a deficient number, since it is larger than the sum of its proper divisors (275921741).

6642635443 is a wasteful number, since it uses less digits than its factorization.

6642635443 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7962.

The product of its digits is 1244160, while the sum is 43.

The square root of 6642635443 is about 81502.3646466776. The cubic root of 6642635443 is about 1879.8079103384.

The spelling of 6642635443 in words is "six billion, six hundred forty-two million, six hundred thirty-five thousand, four hundred forty-three".