840550657 has 2 divisors, whose sum is σ = 840550658. Its totient is φ = 840550656.

The previous prime is 840550631. The next prime is 840550721. The reversal of 840550657 is 756055048.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 822026241 + 18524416 = 28671^2 + 4304^2 .

It is a cyclic number.

It is not a de Polignac number, because 840550657 - 2¹¹ = 840548609 is a prime.

It is a super-3 number, since 3×840550657³ (a number of 28 digits) contains 333 as substring.

It is not a weakly prime, because it can be changed into another prime (840520657) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 420275328 + 420275329.

It is an arithmetic number, because the mean of its divisors is an integer number (420275329).

Almost surely, 2^840550657 is an apocalyptic number.

It is an amenable number.

840550657 is a deficient number, since it is larger than the sum of its proper divisors (1).

840550657 is an equidigital number, since it uses as much as digits as its factorization.

840550657 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 168000, while the sum is 40.

The square root of 840550657 is about 28992.2516717829. The cubic root of 840550657 is about 943.7449281075.

The spelling of 840550657 in words is "eight hundred forty million, five hundred fifty thousand, six hundred fifty-seven".