64128081 has 4 divisors (see below), whose sum is σ = 85504112. Its totient is φ = 42752052.

The previous prime is 64128073. The next prime is 64128089. The reversal of 64128081 is 18082146.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is an interprime number because it is at equal distance from previous prime (64128073) and next prime (64128089).

It is not a de Polignac number, because 64128081 - 2³ = 64128073 is a prime.

It is a super-2 number, since 2×64128081² = 8224821545485122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (64128089) 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 3 ways as a sum of consecutive naturals, for example, 10688011 + ... + 10688016.

It is an arithmetic number, because the mean of its divisors is an integer number (21376028).

Almost surely, 2^64128081 is an apocalyptic number.

It is an amenable number.

64128081 is a deficient number, since it is larger than the sum of its proper divisors (21376031).

64128081 is a wasteful number, since it uses less digits than its factorization.

64128081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21376030.

The product of its (nonzero) digits is 3072, while the sum is 30.

The square root of 64128081 is about 8008.0010614385. The cubic root of 64128081 is about 400.2666576115.

The spelling of 64128081 in words is "sixty-four million, one hundred twenty-eight thousand, eighty-one".