1804381 has 2 divisors, whose sum is σ = 1804382. Its totient is φ = 1804380.

The previous prime is 1804349. The next prime is 1804391. The reversal of 1804381 is 1834081.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1265625 + 538756 = 1125^2 + 734^2 .

It is a cyclic number.

It is not a de Polignac number, because 1804381 - 2⁵ = 1804349 is a prime.

It is a super-2 number, since 2×1804381² = 6511581586322, which contains 22 as substring.

It is an Ulam number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1804321) by changing a digit.

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

It is a good prime.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 902190 + 902191.

It is an arithmetic number, because the mean of its divisors is an integer number (902191).

2^1804381 is an apocalyptic number.

It is an amenable number.

1804381 is a deficient number, since it is larger than the sum of its proper divisors (1).

1804381 is an equidigital number, since it uses as much as digits as its factorization.

1804381 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 768, while the sum is 25.

The square root of 1804381 is about 1343.2724965546. The cubic root of 1804381 is about 121.7426493123.

The spelling of 1804381 in words is "one million, eight hundred four thousand, three hundred eighty-one".