1840221 has 12 divisors (see below), whose sum is σ = 2679040. Its totient is φ = 1217160.

The previous prime is 1840219. The next prime is 1840231. The reversal of 1840221 is 1220481.

It is not a de Polignac number, because 1840221 - 2¹ = 1840219 is a prime.

It is a Duffinian number.

1840221 is a lucky number.

It is a junction number, because it is equal to n+sod(n) for n = 1840194 and 1840203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1840231) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 516 + ... + 1986.

2^1840221 is an apocalyptic number.

It is an amenable number.

1840221 is a deficient number, since it is larger than the sum of its proper divisors (838819).

1840221 is a wasteful number, since it uses less digits than its factorization.

1840221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1616 (or 1613 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

The square root of 1840221 is about 1356.5474558599. The cubic root of 1840221 is about 122.5434192885.

The spelling of 1840221 in words is "one million, eight hundred forty thousand, two hundred twenty-one".