84218917 has 2 divisors, whose sum is σ = 84218918. Its totient is φ = 84218916.

The previous prime is 84218903. The next prime is 84218923. The reversal of 84218917 is 71981248.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 81703521 + 2515396 = 9039^2 + 1586^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-84218917 is a prime.

It is equal to p_4900999 and since 84218917 and 4900999 have the same sum of digits, it is a Honaker prime.

It is a self number, because there is not a number n which added to its sum of digits gives 84218917.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (84218947) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42109458 + 42109459.

It is an arithmetic number, because the mean of its divisors is an integer number (42109459).

Almost surely, 2^84218917 is an apocalyptic number.

It is an amenable number.

84218917 is a deficient number, since it is larger than the sum of its proper divisors (1).

84218917 is an equidigital number, since it uses as much as digits as its factorization.

84218917 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 32256, while the sum is 40.

The square root of 84218917 is about 9177.0865202416. The cubic root of 84218917 is about 438.3320407787.

The spelling of 84218917 in words is "eighty-four million, two hundred eighteen thousand, nine hundred seventeen".