6405017666840 has 64 divisors (see below), whose sum is σ = 15523904340000. Its totient is φ = 2364311872512.

The previous prime is 6405017666821. The next prime is 6405017666851. The reversal of 6405017666840 is 486667105046.

It is a congruent number.

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 15 ways as a sum of consecutive naturals, for example, 386411 + ... + 3599909.

Almost surely, 2^{6405017666840} is an apocalyptic number.

It is an amenable number.

6405017666840 is an abundant number, since it is smaller than the sum of its proper divisors (9118886673160).

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

6405017666840 is a wasteful number, since it uses less digits than its factorization.

6405017666840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3217356 (or 3217352 counting only the distinct ones).

The product of its (nonzero) digits is 5806080, while the sum is 53.

The spelling of 6405017666840 in words is "six trillion, four hundred five billion, seventeen million, six hundred sixty-six thousand, eight hundred forty".