85409821 has 8 divisors (see below), whose sum is σ = 99211904. Its totient is φ = 72007920.

The previous prime is 85409813. The next prime is 85409827. The reversal of 85409821 is 12890458.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 85409821 - 2³ = 85409813 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (85409827) 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 in 7 ways as a sum of consecutive naturals, for example, 99585 + ... + 100438.

It is an arithmetic number, because the mean of its divisors is an integer number (12401488).

Almost surely, 2^85409821 is an apocalyptic number.

It is an amenable number.

85409821 is a deficient number, since it is larger than the sum of its proper divisors (13802083).

85409821 is a wasteful number, since it uses less digits than its factorization.

85409821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 200091.

The product of its (nonzero) digits is 23040, while the sum is 37.

The square root of 85409821 is about 9241.7433961347. The cubic root of 85409821 is about 440.3884671909.

The spelling of 85409821 in words is "eighty-five million, four hundred nine thousand, eight hundred twenty-one".