640199235207168 has 918 divisors, whose sum is σ = 2329641800822349. Its totient is φ = 168843754340352.

The previous prime is 640199235207167. The next prime is 640199235207209. The reversal of 640199235207168 is 861702532991046.

It is a powerful number, because all its prime factors have an exponent greater than 1 and also an Achilles number because it is not a perfect power.

640199235207168 is a `hidden beast` number, since 6 + 4 + 0 + 1 + 9 + 92 + 3 + 520 + 7 + 16 + 8 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 547389286907904 + 92809948299264 = 23396352^2 + 9633792^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=17891328.

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

It is not an unprimeable number, because it can be changed into a prime (640199235207167) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 49246095015930 + ... + 49246095015942.

It is a 1-persistent number, because it is pandigital, but 2⋅640199235207168 = 1280398470414336 is not.

Almost surely, 2^{640199235207168} 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 640199235207168

640199235207168 is an abundant number, since it is smaller than the sum of its proper divisors (1689442565615181).

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

640199235207168 is an frugal number, since it uses more digits than its factorization.

640199235207168 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 112 (or 25 counting only the distinct ones).

The product of its (nonzero) digits is 39191040, while the sum is 63.

The spelling of 640199235207168 in words is "six hundred forty trillion, one hundred ninety-nine billion, two hundred thirty-five million, two hundred seven thousand, one hundred sixty-eight".