83870209 has 2 divisors, whose sum is σ = 83870210. Its totient is φ = 83870208.

The previous prime is 83870173. The next prime is 83870249. The reversal of 83870209 is 90207838.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 80730225 + 3139984 = 8985^2 + 1772^2 .

It is a cyclic number.

It is not a de Polignac number, because 83870209 - 2⁹ = 83869697 is a prime.

It is equal to p_4881916 and since 83870209 and 4881916 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (83870249) 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, 41935104 + 41935105.

It is an arithmetic number, because the mean of its divisors is an integer number (41935105).

Almost surely, 2^83870209 is an apocalyptic number.

It is an amenable number.

83870209 is a deficient number, since it is larger than the sum of its proper divisors (1).

83870209 is an equidigital number, since it uses as much as digits as its factorization.

83870209 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 24192, while the sum is 37.

The square root of 83870209 is about 9158.0679731044. The cubic root of 83870209 is about 437.7262333608.

The spelling of 83870209 in words is "eighty-three million, eight hundred seventy thousand, two hundred nine".