1812641 has 4 divisors (see below), whose sum is σ = 1816212. Its totient is φ = 1809072.

The previous prime is 1812623. The next prime is 1812661. The reversal of 1812641 is 1462181.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 112225 + 1700416 = 335^2 + 1304^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1812641 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1812611) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 866 + ... + 2091.

It is an arithmetic number, because the mean of its divisors is an integer number (454053).

2^1812641 is an apocalyptic number.

It is an amenable number.

1812641 is a deficient number, since it is larger than the sum of its proper divisors (3571).

1812641 is an equidigital number, since it uses as much as digits as its factorization.

1812641 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3570.

The product of its digits is 384, while the sum is 23.

The square root of 1812641 is about 1346.3435668506. The cubic root of 1812641 is about 121.9281355856.

The spelling of 1812641 in words is "one million, eight hundred twelve thousand, six hundred forty-one".