65128788 has 18 divisors (see below), whose sum is σ = 164631194. Its totient is φ = 21709584.

The previous prime is 65128783. The next prime is 65128813. The reversal of 65128788 is 88782156.

65128788 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 only one way, i.e., 46621584 + 18507204 = 6828^2 + 4302^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65128783) 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 5 ways as a sum of consecutive naturals, for example, 904531 + ... + 904602.

Almost surely, 2^65128788 is an apocalyptic number.

It is an amenable number.

65128788 is an abundant number, since it is smaller than the sum of its proper divisors (99502406).

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

65128788 is a wasteful number, since it uses less digits than its factorization.

65128788 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1809143 (or 1809138 counting only the distinct ones).

The product of its digits is 215040, while the sum is 45.

The square root of 65128788 is about 8070.2408885981. The cubic root of 65128788 is about 402.3379500175.

The spelling of 65128788 in words is "sixty-five million, one hundred twenty-eight thousand, seven hundred eighty-eight".