840834581 has 2 divisors, whose sum is σ = 840834582. Its totient is φ = 840834580.

The previous prime is 840834563. The next prime is 840834587. The reversal of 840834581 is 185438048.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 491331556 + 349503025 = 22166^2 + 18695^2 .

It is a cyclic number.

It is not a de Polignac number, because 840834581 - 2¹⁰ = 840833557 is a prime.

It is a super-2 number, since 2×840834581² = 1414005585210891122, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (840834587) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 420417290 + 420417291.

It is an arithmetic number, because the mean of its divisors is an integer number (420417291).

Almost surely, 2^840834581 is an apocalyptic number.

It is an amenable number.

840834581 is a deficient number, since it is larger than the sum of its proper divisors (1).

840834581 is an equidigital number, since it uses as much as digits as its factorization.

840834581 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 122880, while the sum is 41.

The square root of 840834581 is about 28997.1478080173. The cubic root of 840834581 is about 943.8511765802.

The spelling of 840834581 in words is "eight hundred forty million, eight hundred thirty-four thousand, five hundred eighty-one".