57550021 has 2 divisors, whose sum is σ = 57550022. Its totient is φ = 57550020.

The previous prime is 57549991. The next prime is 57550027. The reversal of 57550021 is 12005575.

It is a happy number.

57550021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 40780996 + 16769025 = 6386^2 + 4095^2 .

It is a cyclic number.

It is not a de Polignac number, because 57550021 - 2¹⁹ = 57025733 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (57550027) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 28775010 + 28775011.

It is an arithmetic number, because the mean of its divisors is an integer number (28775011).

Almost surely, 2^57550021 is an apocalyptic number.

It is an amenable number.

57550021 is a deficient number, since it is larger than the sum of its proper divisors (1).

57550021 is an equidigital number, since it uses as much as digits as its factorization.

57550021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1750, while the sum is 25.

The square root of 57550021 is about 7586.1730141093. The cubic root of 57550021 is about 386.0840219967.

Adding to 57550021 its reverse (12005575), we get a palindrome (69555596).

The spelling of 57550021 in words is "fifty-seven million, five hundred fifty thousand, twenty-one".