640440848 has 20 divisors (see below), whose sum is σ = 1241402688. Its totient is φ = 320078880.

The previous prime is 640440841. The next prime is 640440907. The reversal of 640440848 is 848044046.

It is not an unprimeable number, because it can be changed into a prime (640440841) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 35093 + ... + 50123.

Almost surely, 2^640440848 is an apocalyptic number.

It is an amenable number.

640440848 is a deficient number, since it is larger than the sum of its proper divisors (600961840).

640440848 is a wasteful number, since it uses less digits than its factorization.

640440848 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17702 (or 17696 counting only the distinct ones).

The product of its (nonzero) digits is 98304, while the sum is 38.

The square root of 640440848 is about 25306.9328050635. The cubic root of 640440848 is about 861.9717010608.

The spelling of 640440848 in words is "six hundred forty million, four hundred forty thousand, eight hundred forty-eight".