65643040 has 48 divisors (see below), whose sum is σ = 156981888. Its totient is φ = 25935616.

The previous prime is 65643029. The next prime is 65643041. The reversal of 65643040 is 4034656.

It is not an unprimeable number, because it can be changed into a prime (65643041) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10809 + ... + 15751.

It is an arithmetic number, because the mean of its divisors is an integer number (3270456).

Almost surely, 2^65643040 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 65643040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (78490944).

65643040 is an abundant number, since it is smaller than the sum of its proper divisors (91338848).

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

65643040 is a wasteful number, since it uses less digits than its factorization.

65643040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5041 (or 5033 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 28.

The square root of 65643040 is about 8102.0392494729. The cubic root of 65643040 is about 403.3941184409.

Adding to 65643040 its reverse (4034656), we get a palindrome (69677696).

It can be divided in two parts, 6564 and 3040, that added together give a square (9604 = 98²).

The spelling of 65643040 in words is "sixty-five million, six hundred forty-three thousand, forty".