84639389 has 2 divisors, whose sum is σ = 84639390. Its totient is φ = 84639388.

The previous prime is 84639383. The next prime is 84639419. The reversal of 84639389 is 98393648.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 78464164 + 6175225 = 8858^2 + 2485^2 .

It is a cyclic number.

It is not a de Polignac number, because 84639389 - 2⁸ = 84639133 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (84639383) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42319694 + 42319695.

It is an arithmetic number, because the mean of its divisors is an integer number (42319695).

Almost surely, 2^84639389 is an apocalyptic number.

It is an amenable number.

84639389 is a deficient number, since it is larger than the sum of its proper divisors (1).

84639389 is an equidigital number, since it uses as much as digits as its factorization.

84639389 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1119744, while the sum is 50.

The square root of 84639389 is about 9199.9667934183. The cubic root of 84639389 is about 439.0603034274.

The spelling of 84639389 in words is "eighty-four million, six hundred thirty-nine thousand, three hundred eighty-nine".