820111 has 8 divisors (see below), whose sum is σ = 864864. Its totient is φ = 776160.

The previous prime is 820109. The next prime is 820117. The reversal of 820111 is 111028.

820111 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 820111 - 2¹ = 820109 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 820091 and 820100.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (820117) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4065 + ... + 4261.

It is an arithmetic number, because the mean of its divisors is an integer number (108108).

2⁸²⁰¹¹¹ is an apocalyptic number.

820111 is a deficient number, since it is larger than the sum of its proper divisors (44753).

820111 is a wasteful number, since it uses less digits than its factorization.

820111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 401.

The product of its (nonzero) digits is 16, while the sum is 13.

The square root of 820111 is about 905.5998012367. The cubic root of 820111 is about 93.6032394111.

Adding to 820111 its reverse (111028), we get a palindrome (931139).

The spelling of 820111 in words is "eight hundred twenty thousand, one hundred eleven".