57204221 has 2 divisors, whose sum is σ = 57204222. Its totient is φ = 57204220.

The previous prime is 57204209. The next prime is 57204239. The reversal of 57204221 is 12240275.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 51681721 + 5522500 = 7189^2 + 2350^2 .

It is a cyclic number.

It is not a de Polignac number, because 57204221 - 2⁶ = 57204157 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (57204271) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 28602110 + 28602111.

It is an arithmetic number, because the mean of its divisors is an integer number (28602111).

Almost surely, 2^57204221 is an apocalyptic number.

It is an amenable number.

57204221 is a deficient number, since it is larger than the sum of its proper divisors (1).

57204221 is an equidigital number, since it uses as much as digits as its factorization.

57204221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1120, while the sum is 23.

The square root of 57204221 is about 7563.3472087430. The cubic root of 57204221 is about 385.3091821214.

Adding to 57204221 its reverse (12240275), we get a palindrome (69444496).

The spelling of 57204221 in words is "fifty-seven million, two hundred four thousand, two hundred twenty-one".