820611 has 24 divisors (see below), whose sum is σ = 1345344. Its totient is φ = 495720.

The previous prime is 820609. The next prime is 820619. The reversal of 820611 is 116028.

It is not a de Polignac number, because 820611 - 2¹ = 820609 is a prime.

It is a nialpdrome in base 7.

It is not an unprimeable number, because it can be changed into a prime (820619) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2520 + ... + 2826.

It is an arithmetic number, because the mean of its divisors is an integer number (56056).

2⁸²⁰⁶¹¹ is an apocalyptic number.

820611 is a gapful number since it is divisible by the number (81) formed by its first and last digit.

820611 is a deficient number, since it is larger than the sum of its proper divisors (524733).

820611 is a wasteful number, since it uses less digits than its factorization.

820611 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 333 (or 321 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 18.

The square root of 820611 is about 905.8758193042. The cubic root of 820611 is about 93.6222580202.

Adding to 820611 its reverse (116028), we get a palindrome (936639).

It can be divided in two parts, 820 and 611, that added together give a triangular number (1431 = T₅₃).

The spelling of 820611 in words is "eight hundred twenty thousand, six hundred eleven".