221223231 has 20 divisors (see below), whose sum is σ = 332400552. Its totient is φ = 146620368.

The previous prime is 221223221. The next prime is 221223241. The reversal of 221223231 is 132322122.

It is an interprime number because it is at equal distance from previous prime (221223221) and next prime (221223241).

It is not a de Polignac number, because 221223231 - 2⁷ = 221223103 is a prime.

It is a super-2 number, since 2×221223231² = 97879435868158722, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221223221) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 6120 + ... + 21906.

Almost surely, 2^221223231 is an apocalyptic number.

221223231 is a deficient number, since it is larger than the sum of its proper divisors (111177321).

221223231 is a wasteful number, since it uses less digits than its factorization.

221223231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15972 (or 15963 counting only the distinct ones).

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

The square root of 221223231 is about 14873.5749233330. The cubic root of 221223231 is about 604.7978570172.

Adding to 221223231 its reverse (132322122), we get a palindrome (353545353).

The spelling of 221223231 in words is "two hundred twenty-one million, two hundred twenty-three thousand, two hundred thirty-one".