1821646 has 12 divisors (see below), whose sum is σ = 2865672. Its totient is φ = 866844.

The previous prime is 1821641. The next prime is 1821649. The reversal of 1821646 is 6461281.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1821641) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 9055 + ... + 9253.

It is an arithmetic number, because the mean of its divisors is an integer number (238806).

2^1821646 is an apocalyptic number.

1821646 is a deficient number, since it is larger than the sum of its proper divisors (1044026).

1821646 is an equidigital number, since it uses as much as digits as its factorization.

1821646 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 423 (or 224 counting only the distinct ones).

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

The square root of 1821646 is about 1349.6836666419. The cubic root of 1821646 is about 122.1297106495.

The spelling of 1821646 in words is "one million, eight hundred twenty-one thousand, six hundred forty-six".