1220322221 has 4 divisors (see below), whose sum is σ = 1228095132. Its totient is φ = 1212549312.

The previous prime is 1220322217. The next prime is 1220322251. The reversal of 1220322221 is 1222230221.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1222230221 = 61 ⋅20036561.

It can be written as a sum of positive squares in 2 ways, for example, as 200222500 + 1020099721 = 14150^2 + 31939^2 .

It is a cyclic number.

It is not a de Polignac number, because 1220322221 - 2² = 1220322217 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1220322221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1220322211) 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, 3886220 + ... + 3886533.

It is an arithmetic number, because the mean of its divisors is an integer number (307023783).

Almost surely, 2^1220322221 is an apocalyptic number.

It is an amenable number.

1220322221 is a deficient number, since it is larger than the sum of its proper divisors (7772911).

1220322221 is an equidigital number, since it uses as much as digits as its factorization.

1220322221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7772910.

The product of its (nonzero) digits is 192, while the sum is 17.

The square root of 1220322221 is about 34933.1106688196. The cubic root of 1220322221 is about 1068.6237936491.

Adding to 1220322221 its reverse (1222230221), we get a palindrome (2442552442).

The spelling of 1220322221 in words is "one billion, two hundred twenty million, three hundred twenty-two thousand, two hundred twenty-one".