6400991842560 has 864 divisors, whose sum is σ = 26574814506240. Its totient is φ = 1391514550272.

The previous prime is 6400991842559. The next prime is 6400991842577. The reversal of 6400991842560 is 652481990046.

6400991842560 is a `hidden beast` number, since 6 + 400 + 9 + 9 + 184 + 2 + 56 + 0 = 666.

It is a junction number, because it is equal to n+sod(n) for n = 6400991842497 and 6400991842506.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 156663094 + ... + 156703946.

It is an arithmetic number, because the mean of its divisors is an integer number (30757887160).

Almost surely, 2^{6400991842560} is an apocalyptic number.

6400991842560 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 6400991842560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (13287407253120).

6400991842560 is an abundant number, since it is smaller than the sum of its proper divisors (20173822663680).

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

6400991842560 is a wasteful number, since it uses less digits than its factorization.

6400991842560 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40983 (or 40966 counting only the distinct ones).

The product of its (nonzero) digits is 3732480, while the sum is 54.

The spelling of 6400991842560 in words is "six trillion, four hundred billion, nine hundred ninety-one million, eight hundred forty-two thousand, five hundred sixty".