1820449 has 2 divisors, whose sum is σ = 1820450. Its totient is φ = 1820448.

The previous prime is 1820431. The next prime is 1820461. The reversal of 1820449 is 9440281.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1774224 + 46225 = 1332^2 + 215^2 .

It is a cyclic number.

It is not a de Polignac number, because 1820449 - 2¹⁷ = 1689377 is a prime.

It is an Ulam number.

It is not a weakly prime, because it can be changed into another prime (1820419) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 910224 + 910225.

It is an arithmetic number, because the mean of its divisors is an integer number (910225).

2^1820449 is an apocalyptic number.

It is an amenable number.

1820449 is a deficient number, since it is larger than the sum of its proper divisors (1).

1820449 is an equidigital number, since it uses as much as digits as its factorization.

1820449 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2304, while the sum is 28.

The square root of 1820449 is about 1349.2401565326. The cubic root of 1820449 is about 122.1029543907.

The spelling of 1820449 in words is "one million, eight hundred twenty thousand, four hundred forty-nine".