85821601 has 4 divisors (see below), whose sum is σ = 85900932. Its totient is φ = 85742272.

The previous prime is 85821599. The next prime is 85821607. The reversal of 85821601 is 10612858.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 9241600 + 76580001 = 3040^2 + 8751^2 .

It is a cyclic number.

It is not a de Polignac number, because 85821601 - 2¹ = 85821599 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (85821607) 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 3 ways as a sum of consecutive naturals, for example, 38020 + ... + 40213.

It is an arithmetic number, because the mean of its divisors is an integer number (21475233).

Almost surely, 2^85821601 is an apocalyptic number.

It is an amenable number.

85821601 is a deficient number, since it is larger than the sum of its proper divisors (79331).

85821601 is a wasteful number, since it uses less digits than its factorization.

85821601 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 79330.

The product of its (nonzero) digits is 3840, while the sum is 31.

The square root of 85821601 is about 9263.9948726238. The cubic root of 85821601 is about 441.0950701978.

The spelling of 85821601 in words is "eighty-five million, eight hundred twenty-one thousand, six hundred one".