840468247 has 2 divisors, whose sum is σ = 840468248. Its totient is φ = 840468246.

The previous prime is 840468217. The next prime is 840468259. The reversal of 840468247 is 742864048.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-840468247 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (840468217) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 420234123 + 420234124.

It is an arithmetic number, because the mean of its divisors is an integer number (420234124).

Almost surely, 2^840468247 is an apocalyptic number.

840468247 is a deficient number, since it is larger than the sum of its proper divisors (1).

840468247 is an equidigital number, since it uses as much as digits as its factorization.

840468247 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 344064, while the sum is 43.

The square root of 840468247 is about 28990.8303951439. The cubic root of 840468247 is about 943.7140846119.

The spelling of 840468247 in words is "eight hundred forty million, four hundred sixty-eight thousand, two hundred forty-seven".