85901209 has 2 divisors, whose sum is σ = 85901210. Its totient is φ = 85901208.

The previous prime is 85901201. The next prime is 85901243. The reversal of 85901209 is 90210958.

It is an a-pointer prime, because the next prime (85901243) can be obtained adding 85901209 to its sum of digits (34).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 46963609 + 38937600 = 6853^2 + 6240^2 .

It is a cyclic number.

It is not a de Polignac number, because 85901209 - 2³ = 85901201 is a prime.

It is not a weakly prime, because it can be changed into another prime (85901201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42950604 + 42950605.

It is an arithmetic number, because the mean of its divisors is an integer number (42950605).

Almost surely, 2^85901209 is an apocalyptic number.

It is an amenable number.

85901209 is a deficient number, since it is larger than the sum of its proper divisors (1).

85901209 is an equidigital number, since it uses as much as digits as its factorization.

85901209 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6480, while the sum is 34.

The square root of 85901209 is about 9268.2905112000. The cubic root of 85901209 is about 441.2314144440.

The spelling of 85901209 in words is "eighty-five million, nine hundred one thousand, two hundred nine".