1821481 has 2 divisors, whose sum is σ = 1821482. Its totient is φ = 1821480.

The previous prime is 1821433. The next prime is 1821487. The reversal of 1821481 is 1841281.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1155625 + 665856 = 1075^2 + 816^2 .

It is a cyclic number.

It is not a de Polignac number, because 1821481 - 2⁷ = 1821353 is a prime.

It is a super-2 number, since 2×1821481² = 6635586066722, which contains 22 as substring.

It is equal to p₁₃₆₅₅₅ and since 1821481 and 136555 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (1821487) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 910740 + 910741.

It is an arithmetic number, because the mean of its divisors is an integer number (910741).

2^1821481 is an apocalyptic number.

It is an amenable number.

1821481 is a deficient number, since it is larger than the sum of its proper divisors (1).

1821481 is an equidigital number, since it uses as much as digits as its factorization.

1821481 is an evil number, because the sum of its binary digits is even.

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

The square root of 1821481 is about 1349.6225398236. The cubic root of 1821481 is about 122.1260231400.

The spelling of 1821481 in words is "one million, eight hundred twenty-one thousand, four hundred eighty-one".