856290389 has 2 divisors, whose sum is σ = 856290390. Its totient is φ = 856290388.

The previous prime is 856290343. The next prime is 856290469. The reversal of 856290389 is 983092658.

856290389 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 can be written as a sum of positive squares in only one way, i.e., 847392100 + 8898289 = 29110^2 + 2983^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-856290389 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (856290319) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 428145194 + 428145195.

It is an arithmetic number, because the mean of its divisors is an integer number (428145195).

Almost surely, 2^856290389 is an apocalyptic number.

It is an amenable number.

856290389 is a deficient number, since it is larger than the sum of its proper divisors (1).

856290389 is an equidigital number, since it uses as much as digits as its factorization.

856290389 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 933120, while the sum is 50.

The square root of 856290389 is about 29262.4399016897. The cubic root of 856290389 is about 949.5992359448.

The spelling of 856290389 in words is "eight hundred fifty-six million, two hundred ninety thousand, three hundred eighty-nine".