57728215 has 4 divisors (see below), whose sum is σ = 69273864. Its totient is φ = 46182568.

The previous prime is 57728179. The next prime is 57728219. The reversal of 57728215 is 51282775.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 57728215 - 2⁷ = 57728087 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (57728219) 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, 5772817 + ... + 5772826.

It is an arithmetic number, because the mean of its divisors is an integer number (17318466).

Almost surely, 2^57728215 is an apocalyptic number.

57728215 is a deficient number, since it is larger than the sum of its proper divisors (11545649).

57728215 is a wasteful number, since it uses less digits than its factorization.

57728215 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11545648.

The product of its digits is 39200, while the sum is 37.

The square root of 57728215 is about 7597.9085938171. The cubic root of 57728215 is about 386.4820929265.

The spelling of 57728215 in words is "fifty-seven million, seven hundred twenty-eight thousand, two hundred fifteen".