85102009 has 2 divisors, whose sum is σ = 85102010. Its totient is φ = 85102008.

The previous prime is 85101967. The next prime is 85102049. The reversal of 85102009 is 90020158.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 70509609 + 14592400 = 8397^2 + 3820^2 .

It is a cyclic number.

It is not a de Polignac number, because 85102009 - 2¹⁷ = 84970937 is a prime.

It is not a weakly prime, because it can be changed into another prime (85102049) 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, 42551004 + 42551005.

It is an arithmetic number, because the mean of its divisors is an integer number (42551005).

Almost surely, 2^85102009 is an apocalyptic number.

It is an amenable number.

85102009 is a deficient number, since it is larger than the sum of its proper divisors (1).

85102009 is an equidigital number, since it uses as much as digits as its factorization.

85102009 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 720, while the sum is 25.

The square root of 85102009 is about 9225.0750132451. The cubic root of 85102009 is about 439.8587856061.

The spelling of 85102009 in words is "eighty-five million, one hundred two thousand, nine".