7989857 has 2 divisors, whose sum is σ = 7989858. Its totient is φ = 7989856.

The previous prime is 7989851. The next prime is 7989869. The reversal of 7989857 is 7589897.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 5400976 + 2588881 = 2324^2 + 1609^2 .

It is a cyclic number.

It is not a de Polignac number, because 7989857 - 2⁸ = 7989601 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 7989799 and 7989808.

It is not a weakly prime, because it can be changed into another prime (7989851) 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, 3994928 + 3994929.

It is an arithmetic number, because the mean of its divisors is an integer number (3994929).

Almost surely, 2^7989857 is an apocalyptic number.

It is an amenable number.

7989857 is a deficient number, since it is larger than the sum of its proper divisors (1).

7989857 is an equidigital number, since it uses as much as digits as its factorization.

7989857 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1270080, while the sum is 53.

The square root of 7989857 is about 2826.6335100257. The cubic root of 7989857 is about 199.9154392524.

The spelling of 7989857 in words is "seven million, nine hundred eighty-nine thousand, eight hundred fifty-seven".