65665764 has 72 divisors (see below), whose sum is σ = 180107928. Its totient is φ = 20090880.

The previous prime is 65665753. The next prime is 65665771. The reversal of 65665764 is 46756656.

It can be written as a sum of positive squares in 4 ways, for example, as 19289664 + 46376100 = 4392^2 + 6810^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 23784 + ... + 26400.

It is an arithmetic number, because the mean of its divisors is an integer number (2501499).

Almost surely, 2^65665764 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 65665764, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (90053964).

65665764 is an abundant number, since it is smaller than the sum of its proper divisors (114442164).

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

65665764 is a wasteful number, since it uses less digits than its factorization.

65665764 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2685 (or 2680 counting only the distinct ones).

The product of its digits is 907200, while the sum is 45.

The square root of 65665764 is about 8103.4414911197. The cubic root of 65665764 is about 403.4406614325.

The spelling of 65665764 in words is "sixty-five million, six hundred sixty-five thousand, seven hundred sixty-four".