221320233 has 24 divisors (see below), whose sum is σ = 324000768. Its totient is φ = 145569312.

The previous prime is 221320223. The next prime is 221320243. The reversal of 221320233 is 332023122.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (221320223) and next prime (221320243).

It is not a de Polignac number, because 221320233 - 2⁴ = 221320217 is a prime.

It is not an unprimeable number, because it can be changed into a prime (221320213) 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 23 ways as a sum of consecutive naturals, for example, 259035 + ... + 259887.

It is an arithmetic number, because the mean of its divisors is an integer number (13500032).

Almost surely, 2^221320233 is an apocalyptic number.

It is an amenable number.

221320233 is a deficient number, since it is larger than the sum of its proper divisors (102680535).

221320233 is a wasteful number, since it uses less digits than its factorization.

221320233 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1213 (or 1210 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 18.

The square root of 221320233 is about 14876.8354497857. The cubic root of 221320233 is about 604.8862413893.

Adding to 221320233 its reverse (332023122), we get a palindrome (553343355).

The spelling of 221320233 in words is "two hundred twenty-one million, three hundred twenty thousand, two hundred thirty-three".