84267809 has 2 divisors, whose sum is σ = 84267810. Its totient is φ = 84267808.

The previous prime is 84267797. The next prime is 84267811. The reversal of 84267809 is 90876248.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 80550625 + 3717184 = 8975^2 + 1928^2 .

It is a cyclic number.

It is not a de Polignac number, because 84267809 - 2⁸ = 84267553 is a prime.

Together with 84267811, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 84267809.

It is not a weakly prime, because it can be changed into another prime (84267899) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42133904 + 42133905.

It is an arithmetic number, because the mean of its divisors is an integer number (42133905).

Almost surely, 2^84267809 is an apocalyptic number.

It is an amenable number.

84267809 is a deficient number, since it is larger than the sum of its proper divisors (1).

84267809 is an equidigital number, since it uses as much as digits as its factorization.

84267809 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 193536, while the sum is 44.

The square root of 84267809 is about 9179.7499421281. The cubic root of 84267809 is about 438.4168466834.

The spelling of 84267809 in words is "eighty-four million, two hundred sixty-seven thousand, eight hundred nine".