28457213 has 2 divisors, whose sum is σ = 28457214. Its totient is φ = 28457212.

The previous prime is 28457203. The next prime is 28457227. The reversal of 28457213 is 31275482.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 26491609 + 1965604 = 5147^2 + 1402^2 .

It is a cyclic number.

It is not a de Polignac number, because 28457213 - 2¹⁶ = 28391677 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 28457213.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28457203) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14228606 + 14228607.

It is an arithmetic number, because the mean of its divisors is an integer number (14228607).

Almost surely, 2^28457213 is an apocalyptic number.

It is an amenable number.

28457213 is a deficient number, since it is larger than the sum of its proper divisors (1).

28457213 is an equidigital number, since it uses as much as digits as its factorization.

28457213 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 13440, while the sum is 32.

The square root of 28457213 is about 5334.5302511093. The cubic root of 28457213 is about 305.3028006003.

The spelling of 28457213 in words is "twenty-eight million, four hundred fifty-seven thousand, two hundred thirteen".