6404040644 has 6 divisors (see below), whose sum is σ = 11207071134. Its totient is φ = 3202020320.

The previous prime is 6404040619. The next prime is 6404040661. The reversal of 6404040644 is 4460404046.

It can be written as a sum of positive squares in only one way, i.e., 4831918144 + 1572122500 = 69512^2 + 39650^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 6404040644.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 800505077 + ... + 800505084.

It is an arithmetic number, because the mean of its divisors is an integer number (1867845189).

Almost surely, 2^6404040644 is an apocalyptic number.

It is an amenable number.

6404040644 is a deficient number, since it is larger than the sum of its proper divisors (4803030490).

6404040644 is a wasteful number, since it uses less digits than its factorization.

6404040644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1601010165 (or 1601010163 counting only the distinct ones).

The product of its (nonzero) digits is 36864, while the sum is 32.

The square root of 6404040644 is about 80025.2500402217. The cubic root of 6404040644 is about 1857.0261805797.

The spelling of 6404040644 in words is "six billion, four hundred four million, forty thousand, six hundred forty-four".