65009664 has 72 divisors (see below), whose sum is σ = 187813080. Its totient is φ = 21663744.

The previous prime is 65009657. The next prime is 65009687. The reversal of 65009664 is 46690056.

It is a happy number.

65009664 is a `hidden beast` number, since 6 + 500 + 96 + 64 = 666.

It is a tau number, because it is divible by the number of its divisors (72).

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 16669 + ... + 20195.

It is an arithmetic number, because the mean of its divisors is an integer number (2608515).

Almost surely, 2^65009664 is an apocalyptic number.

65009664 is a gapful number since it is divisible by the number (64) 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 65009664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (93906540).

65009664 is an abundant number, since it is smaller than the sum of its proper divisors (122803416).

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

65009664 is a wasteful number, since it uses less digits than its factorization.

65009664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3555 (or 3532 counting only the distinct ones).

The product of its (nonzero) digits is 38880, while the sum is 36.

The square root of 65009664 is about 8062.8570618609. The cubic root of 65009664 is about 402.0925011759.

The spelling of 65009664 in words is "sixty-five million, nine thousand, six hundred sixty-four".