221020231 has 8 divisors (see below), whose sum is σ = 224671104. Its totient is φ = 217384440.

The previous prime is 221020211. The next prime is 221020237. The reversal of 221020231 is 132020122.

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 221020231 - 2⁵ = 221020199 is a prime.

It is a super-2 number, since 2×221020231² = 97699885022586722, 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 (221020237) 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 7 ways as a sum of consecutive naturals, for example, 27940 + ... + 34966.

It is an arithmetic number, because the mean of its divisors is an integer number (28083888).

Almost surely, 2^221020231 is an apocalyptic number.

221020231 is a deficient number, since it is larger than the sum of its proper divisors (3650873).

221020231 is an equidigital number, since it uses as much as digits as its factorization.

221020231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7541.

The product of its (nonzero) digits is 48, while the sum is 13.

The square root of 221020231 is about 14866.7491739116. The cubic root of 221020231 is about 604.6128078294.

Adding to 221020231 its reverse (132020122), we get a palindrome (353040353).

The spelling of 221020231 in words is "two hundred twenty-one million, twenty thousand, two hundred thirty-one".