1821418 has 4 divisors (see below), whose sum is σ = 2732130. Its totient is φ = 910708.

The previous prime is 1821409. The next prime is 1821427. The reversal of 1821418 is 8141281.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 8141281 = 673 ⋅12097.

It is an interprime number because it is at equal distance from previous prime (1821409) and next prime (1821427).

It can be written as a sum of positive squares in only one way, i.e., 1006009 + 815409 = 1003^2 + 903^2 .

It is a junction number, because it is equal to n+sod(n) for n = 1821392 and 1821401.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 455353 + ... + 455356.

2^1821418 is an apocalyptic number.

1821418 is a deficient number, since it is larger than the sum of its proper divisors (910712).

1821418 is an equidigital number, since it uses as much as digits as its factorization.

1821418 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 910711.

The product of its digits is 512, while the sum is 25.

The square root of 1821418 is about 1349.5991997627. The cubic root of 1821418 is about 122.1246151231.

Adding to 1821418 its reverse (8141281), we get a palindrome (9962699).

It can be divided in two parts, 182 and 1418, that added together give a square (1600 = 40²).

The spelling of 1821418 in words is "one million, eight hundred twenty-one thousand, four hundred eighteen".