84809917 has 2 divisors, whose sum is σ = 84809918. Its totient is φ = 84809916.

The previous prime is 84809909. The next prime is 84809951. The reversal of 84809917 is 71990848.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 77898276 + 6911641 = 8826^2 + 2629^2 .

It is a cyclic number.

It is not a de Polignac number, because 84809917 - 2³ = 84809909 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (84809017) 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, 42404958 + 42404959.

It is an arithmetic number, because the mean of its divisors is an integer number (42404959).

Almost surely, 2^84809917 is an apocalyptic number.

It is an amenable number.

84809917 is a deficient number, since it is larger than the sum of its proper divisors (1).

84809917 is an equidigital number, since it uses as much as digits as its factorization.

84809917 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 145152, while the sum is 46.

The square root of 84809917 is about 9209.2299895268. The cubic root of 84809917 is about 439.3549725700.

The spelling of 84809917 in words is "eighty-four million, eight hundred nine thousand, nine hundred seventeen".