84397409 has 2 divisors, whose sum is σ = 84397410. Its totient is φ = 84397408.

The previous prime is 84397399. The next prime is 84397429. The reversal of 84397409 is 90479348.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 80496784 + 3900625 = 8972^2 + 1975^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-84397409 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 84397409.

It is not a weakly prime, because it can be changed into another prime (84397429) 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, 42198704 + 42198705.

It is an arithmetic number, because the mean of its divisors is an integer number (42198705).

Almost surely, 2^84397409 is an apocalyptic number.

It is an amenable number.

84397409 is a deficient number, since it is larger than the sum of its proper divisors (1).

84397409 is an equidigital number, since it uses as much as digits as its factorization.

84397409 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 217728, while the sum is 44.

The square root of 84397409 is about 9186.8062459159. The cubic root of 84397409 is about 438.6414865177.

The spelling of 84397409 in words is "eighty-four million, three hundred ninety-seven thousand, four hundred nine".