856306819 has 2 divisors, whose sum is σ = 856306820. Its totient is φ = 856306818.

The previous prime is 856306817. The next prime is 856306897. The reversal of 856306819 is 918603658.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 856306819 - 2¹ = 856306817 is a prime.

It is a super-2 number, since 2×856306819² = 1466522736531797522, which contains 22 as substring.

Together with 856306817, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (856306817) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 428153409 + 428153410.

It is an arithmetic number, because the mean of its divisors is an integer number (428153410).

Almost surely, 2^856306819 is an apocalyptic number.

856306819 is a deficient number, since it is larger than the sum of its proper divisors (1).

856306819 is an equidigital number, since it uses as much as digits as its factorization.

856306819 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 311040, while the sum is 46.

The square root of 856306819 is about 29262.7206356484. The cubic root of 856306819 is about 949.6053093579.

The spelling of 856306819 in words is "eight hundred fifty-six million, three hundred six thousand, eight hundred nineteen".