56728213 has 2 divisors, whose sum is σ = 56728214. Its totient is φ = 56728212.

The previous prime is 56728211. The next prime is 56728229. The reversal of 56728213 is 31282765.

It is a happy number.

56728213 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 29615364 + 27112849 = 5442^2 + 5207^2 .

It is a cyclic number.

It is not a de Polignac number, because 56728213 - 2¹ = 56728211 is a prime.

Together with 56728211, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (56728211) 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, 28364106 + 28364107.

It is an arithmetic number, because the mean of its divisors is an integer number (28364107).

Almost surely, 2^56728213 is an apocalyptic number.

It is an amenable number.

56728213 is a deficient number, since it is larger than the sum of its proper divisors (1).

56728213 is an equidigital number, since it uses as much as digits as its factorization.

56728213 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 20160, while the sum is 34.

The square root of 56728213 is about 7531.8133938647. The cubic root of 56728213 is about 384.2374584720.

The spelling of 56728213 in words is "fifty-six million, seven hundred twenty-eight thousand, two hundred thirteen".