86856839 has 2 divisors, whose sum is σ = 86856840. Its totient is φ = 86856838.

The previous prime is 86856829. The next prime is 86856841. The reversal of 86856839 is 93865868.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 86856839 - 2¹⁶ = 86791303 is a prime.

It is a super-2 number, since 2×86856839² = 15088220962143842, which contains 22 as substring.

Together with 86856841, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (86856829) 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, 43428419 + 43428420.

It is an arithmetic number, because the mean of its divisors is an integer number (43428420).

Almost surely, 2^86856839 is an apocalyptic number.

86856839 is a deficient number, since it is larger than the sum of its proper divisors (1).

86856839 is an equidigital number, since it uses as much as digits as its factorization.

86856839 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2488320, while the sum is 53.

The square root of 86856839 is about 9319.7016583150. The cubic root of 86856839 is about 442.8615815273.

The spelling of 86856839 in words is "eighty-six million, eight hundred fifty-six thousand, eight hundred thirty-nine".