1321223221 has 8 divisors (see below), whose sum is σ = 1402438104. Its totient is φ = 1240396800.

The previous prime is 1321223213. The next prime is 1321223231. The reversal of 1321223221 is 1223221231.

It can be written as a sum of positive squares in 4 ways, for example, as 929579121 + 391644100 = 30489^2 + 19790^2 .

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 1321223221 - 2³ = 1321223213 is a prime.

It is a super-2 number, since 2×1321223221² = 3491261599419229682, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1321223231) 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, 90090 + ... + 103723.

It is an arithmetic number, because the mean of its divisors is an integer number (175304763).

Almost surely, 2^1321223221 is an apocalyptic number.

It is an amenable number.

1321223221 is a deficient number, since it is larger than the sum of its proper divisors (81214883).

1321223221 is a wasteful number, since it uses less digits than its factorization.

1321223221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 194231.

The product of its digits is 288, while the sum is 19.

The square root of 1321223221 is about 36348.6343759982. The cubic root of 1321223221 is about 1097.3000508507.

Adding to 1321223221 its reverse (1223221231), we get a palindrome (2544444452).

The spelling of 1321223221 in words is "one billion, three hundred twenty-one million, two hundred twenty-three thousand, two hundred twenty-one".