8211985 has 4 divisors (see below), whose sum is σ = 9854388. Its totient is φ = 6569584.

The previous prime is 8211977. The next prime is 8211991. The reversal of 8211985 is 5891128.

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 5803281 + 2408704 = 2409^2 + 1552^2 .

It is a cyclic number.

It is not a de Polignac number, because 8211985 - 2³ = 8211977 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 8211985.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 821194 + ... + 821203.

It is an arithmetic number, because the mean of its divisors is an integer number (2463597).

Almost surely, 2^8211985 is an apocalyptic number.

It is an amenable number.

8211985 is a deficient number, since it is larger than the sum of its proper divisors (1642403).

8211985 is a wasteful number, since it uses less digits than its factorization.

8211985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1642402.

The product of its digits is 5760, while the sum is 34.

The square root of 8211985 is about 2865.6561203327. The cubic root of 8211985 is about 201.7511640386.

The spelling of 8211985 in words is "eight million, two hundred eleven thousand, nine hundred eighty-five".