57305221 has 4 divisors (see below), whose sum is σ = 57543244. Its totient is φ = 57067200.

The previous prime is 57305201. The next prime is 57305263. The reversal of 57305221 is 12250375.

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

It can be written as a sum of positive squares in 2 ways, for example, as 16524225 + 40780996 = 4065^2 + 6386^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-57305221 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 (57305201) 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, 118650 + ... + 119131.

It is an arithmetic number, because the mean of its divisors is an integer number (14385811).

Almost surely, 2^57305221 is an apocalyptic number.

It is an amenable number.

57305221 is a deficient number, since it is larger than the sum of its proper divisors (238023).

57305221 is a wasteful number, since it uses less digits than its factorization.

57305221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 238022.

The product of its (nonzero) digits is 2100, while the sum is 25.

The square root of 57305221 is about 7570.0212020839. The cubic root of 57305221 is about 385.5358165994.

Adding to 57305221 its reverse (12250375), we get a palindrome (69555596).

The spelling of 57305221 in words is "fifty-seven million, three hundred five thousand, two hundred twenty-one".