64128805 has 8 divisors (see below), whose sum is σ = 82874232. Its totient is φ = 47356608.

The previous prime is 64128791. The next prime is 64128809. The reversal of 64128805 is 50882146.

64128805 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 160801 + 63968004 = 401^2 + 7998^2 .

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

It is not a de Polignac number, because 64128805 - 2¹³ = 64120613 is a prime.

It is a super-2 number, since 2×64128805² = 8225007261456050, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64128809) 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, 493234 + ... + 493363.

It is an arithmetic number, because the mean of its divisors is an integer number (10359279).

Almost surely, 2^64128805 is an apocalyptic number.

64128805 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

It is an amenable number.

64128805 is a deficient number, since it is larger than the sum of its proper divisors (18745427).

64128805 is a wasteful number, since it uses less digits than its factorization.

64128805 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 986615.

The product of its (nonzero) digits is 15360, while the sum is 34.

The square root of 64128805 is about 8008.0462661001. The cubic root of 64128805 is about 400.2681639301.

The spelling of 64128805 in words is "sixty-four million, one hundred twenty-eight thousand, eight hundred five".