85387305821 has 4 divisors (see below), whose sum is σ = 85418460444. Its totient is φ = 85356151200.

The previous prime is 85387305797. The next prime is 85387305877. The reversal of 85387305821 is 12850378358.

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 50897616025 + 34489689796 = 225605^2 + 185714^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-85387305821 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 85387305821.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (85327305821) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15573200 + ... + 15578681.

It is an arithmetic number, because the mean of its divisors is an integer number (21354615111).

Almost surely, 2^85387305821 is an apocalyptic number.

It is an amenable number.

85387305821 is a deficient number, since it is larger than the sum of its proper divisors (31154623).

85387305821 is a wasteful number, since it uses less digits than its factorization.

85387305821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31154622.

The product of its (nonzero) digits is 1612800, while the sum is 50.

The spelling of 85387305821 in words is "eighty-five billion, three hundred eighty-seven million, three hundred five thousand, eight hundred twenty-one".