64444978539 has 32 divisors (see below), whose sum is σ = 96754870080. Its totient is φ = 42917921280.

The previous prime is 64444978519. The next prime is 64444978541. The reversal of 64444978539 is 93587944446.

It is a happy number.

64444978539 is a `hidden beast` number, since 6 + 4 + 4 + 4 + 4 + 97 + 8 + 539 = 666.

It is not a de Polignac number, because 64444978539 - 2⁹ = 64444978027 is a prime.

It is not an unprimeable number, because it can be changed into a prime (64444978519) by changing a digit.

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, 2121619 + ... + 2151779.

It is an arithmetic number, because the mean of its divisors is an integer number (3023589690).

Almost surely, 2^64444978539 is an apocalyptic number.

64444978539 is a deficient number, since it is larger than the sum of its proper divisors (32309891541).

64444978539 is an frugal number, since it uses more digits than its factorization.

64444978539 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31159 (or 31141 counting only the distinct ones).

The product of its digits is 104509440, while the sum is 63.

The spelling of 64444978539 in words is "sixty-four billion, four hundred forty-four million, nine hundred seventy-eight thousand, five hundred thirty-nine".