840040847 has 2 divisors, whose sum is σ = 840040848. Its totient is φ = 840040846.

The previous prime is 840040781. The next prime is 840040919. The reversal of 840040847 is 748040048.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 840040847 - 2¹⁴ = 840024463 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (840043847) 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, 420020423 + 420020424.

It is an arithmetic number, because the mean of its divisors is an integer number (420020424).

Almost surely, 2^840040847 is an apocalyptic number.

840040847 is a deficient number, since it is larger than the sum of its proper divisors (1).

840040847 is an equidigital number, since it uses as much as digits as its factorization.

840040847 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 28672, while the sum is 35.

The square root of 840040847 is about 28983.4581615100. The cubic root of 840040847 is about 943.5540897556.

The spelling of 840040847 in words is "eight hundred forty million, forty thousand, eight hundred forty-seven".