64128065 has 8 divisors (see below), whose sum is σ = 77635368. Its totient is φ = 50848000.

The previous prime is 64128049. The next prime is 64128073. The reversal of 64128065 is 56082146.

It is a Cunningham number, because it is equal to 8008²+1.

It can be written as a sum of positive squares in 4 ways, for example, as 1132096 + 62995969 = 1064^2 + 7937^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 64128065 - 2⁴ = 64128049 is a prime.

It is a super-2 number, since 2×64128065² = 8224817441288450, which contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 56186 + ... + 57315.

It is an arithmetic number, because the mean of its divisors is an integer number (9704421).

Almost surely, 2^64128065 is an apocalyptic number.

It is an amenable number.

64128065 is a deficient number, since it is larger than the sum of its proper divisors (13507303).

64128065 is a wasteful number, since it uses less digits than its factorization.

64128065 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 113619.

The product of its (nonzero) digits is 11520, while the sum is 32.

The square root of 64128065 is about 8008.0000624376. Note that the first 4 decimals coincide. The cubic root of 64128065 is about 400.2666243225.

The spelling of 64128065 in words is "sixty-four million, one hundred twenty-eight thousand, sixty-five".