6443987955 has 32 divisors (see below), whose sum is σ = 11170773504. Its totient is φ = 3159399936.

The previous prime is 6443987941. The next prime is 6443987983. The reversal of 6443987955 is 5597893446.

It is not a de Polignac number, because 6443987955 - 2⁴ = 6443987939 is a prime.

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 31 ways as a sum of consecutive naturals, for example, 282879 + ... + 304808.

It is an arithmetic number, because the mean of its divisors is an integer number (349086672).

Almost surely, 2^6443987955 is an apocalyptic number.

6443987955 is a deficient number, since it is larger than the sum of its proper divisors (4726785549).

6443987955 is a wasteful number, since it uses less digits than its factorization.

6443987955 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 587755.

The product of its digits is 32659200, while the sum is 60.

The square root of 6443987955 is about 80274.4539377254. The cubic root of 6443987955 is about 1860.8794502799.

The spelling of 6443987955 in words is "six billion, four hundred forty-three million, nine hundred eighty-seven thousand, nine hundred fifty-five".