57277728 has 72 divisors (see below), whose sum is σ = 169985088. Its totient is φ = 18260352.

The previous prime is 57277721. The next prime is 57277757. The reversal of 57277728 is 82777275.

It is a happy number.

57277728 is a `hidden beast` number, since 572 + 7 + 7 + 72 + 8 = 666.

It is a tau number, because it is divible by the number of its divisors (72).

It is not an unprimeable number, because it can be changed into a prime (57277721) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2301 + ... + 10947.

It is an arithmetic number, because the mean of its divisors is an integer number (2360904).

Almost surely, 2^57277728 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 57277728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (84992544).

57277728 is an abundant number, since it is smaller than the sum of its proper divisors (112707360).

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

57277728 is a wasteful number, since it uses less digits than its factorization.

57277728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8686 (or 8675 counting only the distinct ones).

The product of its digits is 384160, while the sum is 45.

The square root of 57277728 is about 7568.2050712173. The cubic root of 57277728 is about 385.4741512946.

The spelling of 57277728 in words is "fifty-seven million, two hundred seventy-seven thousand, seven hundred twenty-eight".