64965718404840 has 256 divisors, whose sum is σ = 220391962214400. Its totient is φ = 15177451161600.

The previous prime is 64965718404833. The next prime is 64965718404877. The reversal of 64965718404840 is 4840481756946.

It is a Harshad number since it is a multiple of its sum of digits (66).

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 6458484 + ... + 13101276.

It is an arithmetic number, because the mean of its divisors is an integer number (860906102400).

Almost surely, 2^{64965718404840} is an apocalyptic number.

64965718404840 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 64965718404840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (110195981107200).

64965718404840 is an abundant number, since it is smaller than the sum of its proper divisors (155426243809560).

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

64965718404840 is a wasteful number, since it uses less digits than its factorization.

64965718404840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6643088 (or 6643084 counting only the distinct ones).

The product of its (nonzero) digits is 185794560, while the sum is 66.

The spelling of 64965718404840 in words is "sixty-four trillion, nine hundred sixty-five billion, seven hundred eighteen million, four hundred four thousand, eight hundred forty".