221032021 has 4 divisors (see below), whose sum is σ = 252608032. Its totient is φ = 189456012.

The previous prime is 221032003. The next prime is 221032037. The reversal of 221032021 is 120230122.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 221032021 - 2¹¹ = 221029973 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 221031992 and 221032010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221032051) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15787995 + ... + 15788008.

It is an arithmetic number, because the mean of its divisors is an integer number (63152008).

Almost surely, 2^221032021 is an apocalyptic number.

It is an amenable number.

221032021 is a deficient number, since it is larger than the sum of its proper divisors (31576011).

221032021 is an equidigital number, since it uses as much as digits as its factorization.

221032021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31576010.

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

The square root of 221032021 is about 14867.1456910868. The cubic root of 221032021 is about 604.6235583660.

Adding to 221032021 its reverse (120230122), we get a palindrome (341262143).

The spelling of 221032021 in words is "two hundred twenty-one million, thirty-two thousand, twenty-one".