1221320223 has 12 divisors (see below), whose sum is σ = 1793050168. Its totient is φ = 800865360.

The previous prime is 1221320197. The next prime is 1221320227. The reversal of 1221320223 is 3220231221.

1221320223 is a `hidden beast` number, since 122 + 1 + 320 + 223 = 666.

It is not a de Polignac number, because 1221320223 - 2¹³ = 1221312031 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1221320196 and 1221320205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221320227) 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, 1111765 + ... + 1112862.

Almost surely, 2^1221320223 is an apocalyptic number.

1221320223 is a deficient number, since it is larger than the sum of its proper divisors (571729945).

1221320223 is a wasteful number, since it uses less digits than its factorization.

1221320223 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2224694 (or 2224691 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 18.

The square root of 1221320223 is about 34947.3922203074. The cubic root of 1221320223 is about 1068.9150276815.

Adding to 1221320223 its reverse (3220231221), we get a palindrome (4441551444).

The spelling of 1221320223 in words is "one billion, two hundred twenty-one million, three hundred twenty thousand, two hundred twenty-three".