85221909 has 16 divisors (see below), whose sum is σ = 126403200. Its totient is φ = 56747808.

The previous prime is 85221907. The next prime is 85221931. The reversal of 85221909 is 90912258.

It is not a de Polignac number, because 85221909 - 2¹ = 85221907 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (85221907) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 34417 + ... + 36809.

It is an arithmetic number, because the mean of its divisors is an integer number (7900200).

Almost surely, 2^85221909 is an apocalyptic number.

It is an amenable number.

85221909 is a deficient number, since it is larger than the sum of its proper divisors (41181291).

85221909 is a wasteful number, since it uses less digits than its factorization.

85221909 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3721 (or 3715 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 36.

The square root of 85221909 is about 9231.5713180368. The cubic root of 85221909 is about 440.0652606369.

The spelling of 85221909 in words is "eighty-five million, two hundred twenty-one thousand, nine hundred nine".