856534979 has 2 divisors, whose sum is σ = 856534980. Its totient is φ = 856534978.

The previous prime is 856534969. The next prime is 856535023. The reversal of 856534979 is 979435658.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 856534979 - 2⁴ = 856534963 is a prime.

It is not a weakly prime, because it can be changed into another prime (856534949) 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, 428267489 + 428267490.

It is an arithmetic number, because the mean of its divisors is an integer number (428267490).

Almost surely, 2^856534979 is an apocalyptic number.

856534979 is a deficient number, since it is larger than the sum of its proper divisors (1).

856534979 is an equidigital number, since it uses as much as digits as its factorization.

856534979 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 8164800, while the sum is 56.

The square root of 856534979 is about 29266.6188515175. The cubic root of 856534979 is about 949.6896415554.

The spelling of 856534979 in words is "eight hundred fifty-six million, five hundred thirty-four thousand, nine hundred seventy-nine".