1213221 has 8 divisors (see below), whose sum is σ = 1624480. Its totient is φ = 805392.

The previous prime is 1213213. The next prime is 1213241. The reversal of 1213221 is 1223121.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1213221 - 2³ = 1213213 is a prime.

It is a Duffinian number.

It is a Curzon number.

1213221 is a lucky number.

It is a junction number, because it is equal to n+sod(n) for n = 1213197 and 1213206.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1213241) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 135 + ... + 1563.

It is an arithmetic number, because the mean of its divisors is an integer number (203060).

2^1213221 is an apocalyptic number.

It is an amenable number.

1213221 is a deficient number, since it is larger than the sum of its proper divisors (411259).

1213221 is a wasteful number, since it uses less digits than its factorization.

1213221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1715.

The product of its digits is 24, while the sum is 12.

The square root of 1213221 is about 1101.4631178573. The cubic root of 1213221 is about 106.6546937516.

Adding to 1213221 its reverse (1223121), we get a palindrome (2436342).

The spelling of 1213221 in words is "one million, two hundred thirteen thousand, two hundred twenty-one".