640444004004 has 72 divisors (see below), whose sum is σ = 1749420543360. Its totient is φ = 181818471744.

The previous prime is 640444003981. The next prime is 640444004023. The reversal of 640444004004 is 400400444046.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3376444 + ... + 3561075.

Almost surely, 2^640444004004 is an apocalyptic number.

It is an amenable number.

640444004004 is an abundant number, since it is smaller than the sum of its proper divisors (1108976539356).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

640444004004 is a wasteful number, since it uses less digits than its factorization.

640444004004 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6937697 (or 6937688 counting only the distinct ones).

The product of its (nonzero) digits is 24576, while the sum is 30.

The spelling of 640444004004 in words is "six hundred forty billion, four hundred forty-four million, four thousand, four".