856284409 has 2 divisors, whose sum is σ = 856284410. Its totient is φ = 856284408.

The previous prime is 856284367. The next prime is 856284427. The reversal of 856284409 is 904482658.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 430770025 + 425514384 = 20755^2 + 20628^2 .

It is a cyclic number.

It is not a de Polignac number, because 856284409 - 2¹³ = 856276217 is a prime.

It is not a weakly prime, because it can be changed into another prime (856284469) 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, 428142204 + 428142205.

It is an arithmetic number, because the mean of its divisors is an integer number (428142205).

Almost surely, 2^856284409 is an apocalyptic number.

It is an amenable number.

856284409 is a deficient number, since it is larger than the sum of its proper divisors (1).

856284409 is an equidigital number, since it uses as much as digits as its factorization.

856284409 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 552960, while the sum is 46.

The square root of 856284409 is about 29262.3377227453. The cubic root of 856284409 is about 949.5970253954.

The spelling of 856284409 in words is "eight hundred fifty-six million, two hundred eighty-four thousand, four hundred nine".