57220309 has 2 divisors, whose sum is σ = 57220310. Its totient is φ = 57220308.

The previous prime is 57220271. The next prime is 57220333. The reversal of 57220309 is 90302275.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 43270084 + 13950225 = 6578^2 + 3735^2 .

It is a cyclic number.

It is not a de Polignac number, because 57220309 - 2¹³ = 57212117 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (57220369) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 28610154 + 28610155.

It is an arithmetic number, because the mean of its divisors is an integer number (28610155).

Almost surely, 2^57220309 is an apocalyptic number.

It is an amenable number.

57220309 is a deficient number, since it is larger than the sum of its proper divisors (1).

57220309 is an equidigital number, since it uses as much as digits as its factorization.

57220309 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3780, while the sum is 28.

The square root of 57220309 is about 7564.4106842503. The cubic root of 57220309 is about 385.3452999288.

The spelling of 57220309 in words is "fifty-seven million, two hundred twenty thousand, three hundred nine".