6400220648 has 8 divisors (see below), whose sum is σ = 12000413730. Its totient is φ = 3200110320.

The previous prime is 6400220647. The next prime is 6400220657. The reversal of 6400220648 is 8460220046.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 4711175044 + 1689045604 = 68638^2 + 41098^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is not an unprimeable number, because it can be changed into a prime (6400220641) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 400013783 + ... + 400013798.

Almost surely, 2^6400220648 is an apocalyptic number.

It is an amenable number.

6400220648 is a deficient number, since it is larger than the sum of its proper divisors (5600193082).

6400220648 is a wasteful number, since it uses less digits than its factorization.

6400220648 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 800027587 (or 800027583 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 32.

The square root of 6400220648 is about 80001.3790381141. The cubic root of 6400220648 is about 1856.6568698102.

The spelling of 6400220648 in words is "six billion, four hundred million, two hundred twenty thousand, six hundred forty-eight".