641687328505440 has 1152 divisors, whose sum is σ = 2650947594946560. Its totient is φ = 138074360610816.

The previous prime is 641687328505439. The next prime is 641687328505463. The reversal of 641687328505440 is 44505823786146.

641687328505440 is a `hidden beast` number, since 6 + 4 + 1 + 6 + 8 + 7 + 3 + 2 + 85 + 0 + 544 + 0 = 666.

641687328505440 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 80281158084 + ... + 80281166076.

It is an arithmetic number, because the mean of its divisors is an integer number (2301169787280).

Almost surely, 2^{641687328505440} is an apocalyptic number.

641687328505440 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 641687328505440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1325473797473280).

641687328505440 is an abundant number, since it is smaller than the sum of its proper divisors (2009260266441120).

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

641687328505440 is a wasteful number, since it uses less digits than its factorization.

641687328505440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10636 (or 10625 counting only the distinct ones).

The product of its (nonzero) digits is 154828800, while the sum is 63.

The spelling of 641687328505440 in words is "six hundred forty-one trillion, six hundred eighty-seven billion, three hundred twenty-eight million, five hundred five thousand, four hundred forty".