820242 has 12 divisors (see below), whose sum is σ = 1777230. Its totient is φ = 273408.

The previous prime is 820241. The next prime is 820243. The reversal of 820242 is 242028.

It is an interprime number because it is at equal distance from previous prime (820241) and next prime (820243).

It can be written as a sum of positive squares in only one way, i.e., 505521 + 314721 = 711^2 + 561^2 .

It is a Harshad number since it is a multiple of its sum of digits (18), and also a Moran number because the ratio is a prime number: 45569 = 820242 / (8 + 2 + 0 + 2 + 4 + 2).

It is a zygodrome in base 3.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (820241) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 22767 + ... + 22802.

2⁸²⁰²⁴² is an apocalyptic number.

820242 is an abundant number, since it is smaller than the sum of its proper divisors (956988).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

820242 is a wasteful number, since it uses less digits than its factorization.

820242 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45577 (or 45574 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 18.

The square root of 820242 is about 905.6721261030. The cubic root of 820242 is about 93.6082230339.

The spelling of 820242 in words is "eight hundred twenty thousand, two hundred forty-two".