1820213 has 2 divisors, whose sum is σ = 1820214. Its totient is φ = 1820212.

The previous prime is 1820201. The next prime is 1820237. The reversal of 1820213 is 3120281.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1085764 + 734449 = 1042^2 + 857^2 .

It is an emirp because it is prime and its reverse (3120281) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1820213 - 2⁸ = 1819957 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1820191 and 1820200.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1820293) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 910106 + 910107.

It is an arithmetic number, because the mean of its divisors is an integer number (910107).

2^1820213 is an apocalyptic number.

It is an amenable number.

1820213 is a deficient number, since it is larger than the sum of its proper divisors (1).

1820213 is an equidigital number, since it uses as much as digits as its factorization.

1820213 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 96, while the sum is 17.

The square root of 1820213 is about 1349.1526970658. The cubic root of 1820213 is about 122.0976777542.

Adding to 1820213 its reverse (3120281), we get a palindrome (4940494).

The spelling of 1820213 in words is "one million, eight hundred twenty thousand, two hundred thirteen".