819220 has 12 divisors (see below), whose sum is σ = 1720404. Its totient is φ = 327680.

The previous prime is 819187. The next prime is 819229. The reversal of 819220 is 22918.

It can be written as a sum of positive squares in 2 ways, for example, as 544644 + 274576 = 738^2 + 524^2 .

It is a super-2 number, since 2×819220² = 1342242816800, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 819191 and 819200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (819229) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20461 + ... + 20500.

It is an arithmetic number, because the mean of its divisors is an integer number (143367).

2⁸¹⁹²²⁰ is an apocalyptic number.

It is an amenable number.

819220 is an abundant number, since it is smaller than the sum of its proper divisors (901184).

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

819220 is a wasteful number, since it uses less digits than its factorization.

819220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40970 (or 40968 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 22.

The square root of 819220 is about 905.1077283948. The cubic root of 819220 is about 93.5693290796.

The spelling of 819220 in words is "eight hundred nineteen thousand, two hundred twenty".