65005720 has 64 divisors (see below), whose sum is σ = 158760000. Its totient is φ = 23812608.

The previous prime is 65005679. The next prime is 65005727. The reversal of 65005720 is 2750056.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65005727) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 77061 + ... + 77899.

It is an arithmetic number, because the mean of its divisors is an integer number (2480625).

Almost surely, 2^65005720 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 65005720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (79380000).

65005720 is an abundant number, since it is smaller than the sum of its proper divisors (93754280).

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

65005720 is a wasteful number, since it uses less digits than its factorization.

65005720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1012 (or 1008 counting only the distinct ones).

The product of its (nonzero) digits is 2100, while the sum is 25.

The square root of 65005720 is about 8062.6124798356. The cubic root of 65005720 is about 402.0843696419.

Adding to 65005720 its reverse (2750056), we get a palindrome (67755776).

The spelling of 65005720 in words is "sixty-five million, five thousand, seven hundred twenty".