640916538458112 has 1224 divisors, whose sum is σ = 2226199036319856. Its totient is φ = 177028624023552.

The previous prime is 640916538458069. The next prime is 640916538458201. The reversal of 640916538458112 is 211854835619046.

It is a happy number.

640916538458112 is a `hidden beast` number, since 6 + 4 + 0 + 9 + 1 + 6 + 5 + 38 + 4 + 581 + 12 = 666.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a self number, because there is not a number n which added to its sum of digits gives 640916538458112.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 174304196818 + ... + 174304200494.

Almost surely, 2^{640916538458112} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 640916538458112, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1113099518159928).

640916538458112 is an abundant number, since it is smaller than the sum of its proper divisors (1585282497861744).

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

640916538458112 is a wasteful number, since it uses less digits than its factorization.

640916538458112 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3929 (or 3889 counting only the distinct ones).

The product of its (nonzero) digits is 49766400, while the sum is 63.

The spelling of 640916538458112 in words is "six hundred forty trillion, nine hundred sixteen billion, five hundred thirty-eight million, four hundred fifty-eight thousand, one hundred twelve".