641811340800 has 1200 divisors, whose sum is σ = 2734839816192. Its totient is φ = 145616486400.

The previous prime is 641811340763. The next prime is 641811340813. The reversal of 641811340800 is 8043118146.

It is a happy number.

641811340800 is a `hidden beast` number, since 64 + 181 + 1 + 340 + 80 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (1200).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 119 ways as a sum of consecutive naturals, for example, 1386201369 + ... + 1386201831.

Almost surely, 2^641811340800 is an apocalyptic number.

641811340800 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 641811340800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1367419908096).

641811340800 is an abundant number, since it is smaller than the sum of its proper divisors (2093028475392).

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

641811340800 is a wasteful number, since it uses less digits than its factorization.

641811340800 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 701 (or 671 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 36.

Adding to 641811340800 its reverse (8043118146), we get a palindrome (649854458946).

The spelling of 641811340800 in words is "six hundred forty-one billion, eight hundred eleven million, three hundred forty thousand, eight hundred".