856215287 has 2 divisors, whose sum is σ = 856215288. Its totient is φ = 856215286.

The previous prime is 856215263. The next prime is 856215317. The reversal of 856215287 is 782512658.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 856215287 - 2²⁸ = 587779831 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 (856211287) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 428107643 + 428107644.

It is an arithmetic number, because the mean of its divisors is an integer number (428107644).

Almost surely, 2^856215287 is an apocalyptic number.

856215287 is a deficient number, since it is larger than the sum of its proper divisors (1).

856215287 is an equidigital number, since it uses as much as digits as its factorization.

856215287 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 268800, while the sum is 44.

The square root of 856215287 is about 29261.1566244398. The cubic root of 856215287 is about 949.5714732108.

The spelling of 856215287 in words is "eight hundred fifty-six million, two hundred fifteen thousand, two hundred eighty-seven".