840513257 has 2 divisors, whose sum is σ = 840513258. Its totient is φ = 840513256.

The previous prime is 840513251. The next prime is 840513277. The reversal of 840513257 is 752315048.

It is a happy number.

840513257 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., 526656601 + 313856656 = 22949^2 + 17716^2 .

It is a cyclic number.

It is not a de Polignac number, because 840513257 - 2¹⁴ = 840496873 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (840513251) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 420256628 + 420256629.

It is an arithmetic number, because the mean of its divisors is an integer number (420256629).

Almost surely, 2^840513257 is an apocalyptic number.

It is an amenable number.

840513257 is a deficient number, since it is larger than the sum of its proper divisors (1).

840513257 is an equidigital number, since it uses as much as digits as its factorization.

840513257 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 33600, while the sum is 35.

The square root of 840513257 is about 28991.6066646883. The cubic root of 840513257 is about 943.7309307025.

The spelling of 840513257 in words is "eight hundred forty million, five hundred thirteen thousand, two hundred fifty-seven".