820455 has 16 divisors (see below), whose sum is σ = 1330560. Its totient is φ = 431648.

The previous prime is 820441. The next prime is 820459. The reversal of 820455 is 554028.

820455 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is not a de Polignac number, because 820455 - 2⁹ = 819943 is a prime.

820455 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (820459) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 916 + ... + 1574.

It is an arithmetic number, because the mean of its divisors is an integer number (83160).

2⁸²⁰⁴⁵⁵ is an apocalyptic number.

820455 is a deficient number, since it is larger than the sum of its proper divisors (510105).

820455 is a wasteful number, since it uses less digits than its factorization.

820455 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 750.

The product of its (nonzero) digits is 1600, while the sum is 24.

The square root of 820455 is about 905.7897106945. The cubic root of 820455 is about 93.6163250435.

It can be divided in two parts, 820 and 455, that added together give a triangular number (1275 = T₅₀).

The spelling of 820455 in words is "eight hundred twenty thousand, four hundred fifty-five".