1683221 has 4 divisors (see below), whose sum is σ = 1782252. Its totient is φ = 1584192.

The previous prime is 1683169. The next prime is 1683223. The reversal of 1683221 is 1223861.

1683221 = T₂₃₁ + T₂₃₂ + ... + T₂₈₁.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1223861 = 293 ⋅4177.

It can be written as a sum of positive squares in 2 ways, for example, as 448900 + 1234321 = 670^2 + 1111^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1683221 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1683223) 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, 49490 + ... + 49523.

It is an arithmetic number, because the mean of its divisors is an integer number (445563).

2^1683221 is an apocalyptic number.

It is an amenable number.

1683221 is a deficient number, since it is larger than the sum of its proper divisors (99031).

1683221 is an equidigital number, since it uses as much as digits as its factorization.

1683221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 99030.

The product of its digits is 576, while the sum is 23.

The square root of 1683221 is about 1297.3900724146. The cubic root of 1683221 is about 118.9543642539.

The spelling of 1683221 in words is "one million, six hundred eighty-three thousand, two hundred twenty-one".