57220221 has 4 divisors (see below), whose sum is σ = 76293632. Its totient is φ = 38146812.

The previous prime is 57220217. The next prime is 57220259. The reversal of 57220221 is 12202275.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 57220221 - 2² = 57220217 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 (57220201) 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, 9536701 + ... + 9536706.

It is an arithmetic number, because the mean of its divisors is an integer number (19073408).

Almost surely, 2^57220221 is an apocalyptic number.

It is an amenable number.

57220221 is a deficient number, since it is larger than the sum of its proper divisors (19073411).

57220221 is a wasteful number, since it uses less digits than its factorization.

57220221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19073410.

The product of its (nonzero) digits is 560, while the sum is 21.

The square root of 57220221 is about 7564.4048675358. The cubic root of 57220221 is about 385.3451023858.

Adding to 57220221 its reverse (12202275), we get a palindrome (69422496).

The spelling of 57220221 in words is "fifty-seven million, two hundred twenty thousand, two hundred twenty-one".