646589959 has 2 divisors, whose sum is σ = 646589960. Its totient is φ = 646589958.

The previous prime is 646589939. The next prime is 646589989. The reversal of 646589959 is 959985646.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-646589959 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 646589897 and 646589906.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (646589929) 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, 323294979 + 323294980.

It is an arithmetic number, because the mean of its divisors is an integer number (323294980).

Almost surely, 2^646589959 is an apocalyptic number.

646589959 is a deficient number, since it is larger than the sum of its proper divisors (1).

646589959 is an equidigital number, since it uses as much as digits as its factorization.

646589959 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 20995200, while the sum is 61.

The square root of 646589959 is about 25428.1332189369. The cubic root of 646589959 is about 864.7216224730.

The spelling of 646589959 in words is "six hundred forty-six million, five hundred eighty-nine thousand, nine hundred fifty-nine".