6440767660 has 24 divisors (see below), whose sum is σ = 13529582640. Its totient is φ = 2575550784.

The previous prime is 6440767639. The next prime is 6440767709. The reversal of 6440767660 is 667670446.

It is a self number, because there is not a number n which added to its sum of digits gives 6440767660.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 25282 + ... + 116278.

It is an arithmetic number, because the mean of its divisors is an integer number (563732610).

Almost surely, 2^6440767660 is an apocalyptic number.

It is an amenable number.

6440767660 is an abundant number, since it is smaller than the sum of its proper divisors (7088814980).

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

6440767660 is a wasteful number, since it uses less digits than its factorization.

6440767660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 94545 (or 94543 counting only the distinct ones).

The product of its (nonzero) digits is 1016064, while the sum is 46.

The square root of 6440767660 is about 80254.3933999878. The cubic root of 6440767660 is about 1860.5694155961.

The spelling of 6440767660 in words is "six billion, four hundred forty million, seven hundred sixty-seven thousand, six hundred sixty".