64540128 has 24 divisors (see below), whose sum is σ = 169418088. Its totient is φ = 21513344.

The previous prime is 64540123. The next prime is 64540129. The reversal of 64540128 is 82104546.

It is a tau number, because it is divible by the number of its divisors (24).

It is a junction number, because it is equal to n+sod(n) for n = 64540095 and 64540104.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64540123) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 336051 + ... + 336242.

It is an arithmetic number, because the mean of its divisors is an integer number (7059087).

Almost surely, 2^64540128 is an apocalyptic number.

It is an amenable number.

64540128 is an abundant number, since it is smaller than the sum of its proper divisors (104877960).

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

64540128 is a wasteful number, since it uses less digits than its factorization.

64540128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 672306 (or 672298 counting only the distinct ones).

The product of its (nonzero) digits is 7680, while the sum is 30.

The square root of 64540128 is about 8033.6870738161. The cubic root of 64540128 is about 401.1221158631.

The spelling of 64540128 in words is "sixty-four million, five hundred forty thousand, one hundred twenty-eight".