65780064 has 144 divisors (see below), whose sum is σ = 217421568. Its totient is φ = 18475776.

The previous prime is 65780063. The next prime is 65780093. The reversal of 65780064 is 46008756.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (144).

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65780063) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 134829 + ... + 135315.

It is an arithmetic number, because the mean of its divisors is an integer number (1509872).

Almost surely, 2^65780064 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 65780064, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (108710784).

65780064 is an abundant number, since it is smaller than the sum of its proper divisors (151641504).

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

65780064 is a wasteful number, since it uses less digits than its factorization.

65780064 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 577 (or 566 counting only the distinct ones).

The product of its (nonzero) digits is 40320, while the sum is 36.

The square root of 65780064 is about 8110.4909839047. The cubic root of 65780064 is about 403.6746064657.

The spelling of 65780064 in words is "sixty-five million, seven hundred eighty thousand, sixty-four".