64809605988 has 216 divisors, whose sum is σ = 182640931200. Its totient is φ = 19336458240.

The previous prime is 64809605957. The next prime is 64809605999. The reversal of 64809605988 is 88950690846.

64809605988 is a `hidden beast` number, since 6 + 480 + 9 + 60 + 5 + 98 + 8 = 666.

It is a super-2 number, since 2×64809605988² (a number of 22 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 47618428 + ... + 47619788.

Almost surely, 2^64809605988 is an apocalyptic number.

64809605988 is a gapful number since it is divisible by the number (68) 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 64809605988, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (91320465600).

64809605988 is an abundant number, since it is smaller than the sum of its proper divisors (117831325212).

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

64809605988 is a wasteful number, since it uses less digits than its factorization.

64809605988 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1627 (or 1605 counting only the distinct ones).

The product of its (nonzero) digits is 29859840, while the sum is 63.

The spelling of 64809605988 in words is "sixty-four billion, eight hundred nine million, six hundred five thousand, nine hundred eighty-eight".