840315247 has 2 divisors, whose sum is σ = 840315248. Its totient is φ = 840315246.

The previous prime is 840315241. The next prime is 840315313. The reversal of 840315247 is 742513048.

840315247 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 is a cyclic number.

It is not a de Polignac number, because 840315247 - 2²³ = 831926639 is a prime.

It is a super-2 number, since 2×840315247² = 1412259428681342018, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (840315241) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 420157623 + 420157624.

It is an arithmetic number, because the mean of its divisors is an integer number (420157624).

Almost surely, 2^840315247 is an apocalyptic number.

840315247 is a deficient number, since it is larger than the sum of its proper divisors (1).

840315247 is an equidigital number, since it uses as much as digits as its factorization.

840315247 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 26880, while the sum is 34.

The square root of 840315247 is about 28988.1915096475. The cubic root of 840315247 is about 943.6568161317.

The spelling of 840315247 in words is "eight hundred forty million, three hundred fifteen thousand, two hundred forty-seven".