856633489 has 2 divisors, whose sum is σ = 856633490. Its totient is φ = 856633488.

The previous prime is 856633471. The next prime is 856633501. The reversal of 856633489 is 984336658.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 666414225 + 190219264 = 25815^2 + 13792^2 .

It is a cyclic number.

It is not a de Polignac number, because 856633489 - 2¹⁷ = 856502417 is a prime.

It is not a weakly prime, because it can be changed into another prime (856633889) 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, 428316744 + 428316745.

It is an arithmetic number, because the mean of its divisors is an integer number (428316745).

Almost surely, 2^856633489 is an apocalyptic number.

It is an amenable number.

856633489 is a deficient number, since it is larger than the sum of its proper divisors (1).

856633489 is an equidigital number, since it uses as much as digits as its factorization.

856633489 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3732480, while the sum is 52.

The square root of 856633489 is about 29268.3017785453. The cubic root of 856633489 is about 949.7260480624.

The spelling of 856633489 in words is "eight hundred fifty-six million, six hundred thirty-three thousand, four hundred eighty-nine".