6640507640400 has 120 divisors (see below), whose sum is σ = 21482371346784. Its totient is φ = 1753269312000.

The previous prime is 6640507640387. The next prime is 6640507640471. The reversal of 6640507640400 is 40467050466.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (120).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 27273634 + ... + 27516033.

Almost surely, 2^{6640507640400} is an apocalyptic number.

6640507640400 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

6640507640400 is an abundant number, since it is smaller than the sum of its proper divisors (14841863706384).

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

6640507640400 is a wasteful number, since it uses less digits than its factorization.

6640507640400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 54789789 (or 54789778 counting only the distinct ones).

The product of its (nonzero) digits is 483840, while the sum is 42.

The spelling of 6640507640400 in words is "six trillion, six hundred forty billion, five hundred seven million, six hundred forty thousand, four hundred".