65491280 has 40 divisors (see below), whose sum is σ = 157523400. Its totient is φ = 25292288.

The previous prime is 65491277. The next prime is 65491289. The reversal of 65491280 is 8219456.

65491280 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 10816 + 65480464 = 104^2 + 8092^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a self number, because there is not a number n which added to its sum of digits gives 65491280.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65491289) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11795 + ... + 16434.

It is an arithmetic number, because the mean of its divisors is an integer number (3938085).

Almost surely, 2^65491280 is an apocalyptic number.

It is an amenable number.

65491280 is an abundant number, since it is smaller than the sum of its proper divisors (92032120).

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

65491280 is a wasteful number, since it uses less digits than its factorization.

65491280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28271 (or 28265 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 35.

The square root of 65491280 is about 8092.6682867890. The cubic root of 65491280 is about 403.0830099084.

The spelling of 65491280 in words is "sixty-five million, four hundred ninety-one thousand, two hundred eighty".