1215221 has 8 divisors (see below), whose sum is σ = 1462080. Its totient is φ = 986688.

The previous prime is 1215209. The next prime is 1215229. The reversal of 1215221 is 1225121.

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

It is a cyclic number.

It is not a de Polignac number, because 1215221 - 2⁶ = 1215157 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1215196 and 1215205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1215229) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4436 + ... + 4701.

It is an arithmetic number, because the mean of its divisors is an integer number (182760).

2^1215221 is an apocalyptic number.

It is an amenable number.

1215221 is a deficient number, since it is larger than the sum of its proper divisors (246859).

1215221 is an equidigital number, since it uses as much as digits as its factorization.

1215221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9163.

The product of its digits is 40, while the sum is 14.

The square root of 1215221 is about 1102.3706273300. The cubic root of 1215221 is about 106.7132684826.

The spelling of 1215221 in words is "one million, two hundred fifteen thousand, two hundred twenty-one".