43031221 has 4 divisors (see below), whose sum is σ = 43576000. Its totient is φ = 42486444.

The previous prime is 43031213. The next prime is 43031243. The reversal of 43031221 is 12213034.

It is a happy number.

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 43031221 - 2³ = 43031213 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 43031195 and 43031204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (43031201) 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, 272271 + ... + 272428.

It is an arithmetic number, because the mean of its divisors is an integer number (10894000).

Almost surely, 2^43031221 is an apocalyptic number.

It is an amenable number.

43031221 is a deficient number, since it is larger than the sum of its proper divisors (544779).

43031221 is an equidigital number, since it uses as much as digits as its factorization.

43031221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 544778.

The product of its (nonzero) digits is 144, while the sum is 16.

The square root of 43031221 is about 6559.8186712744. The cubic root of 43031221 is about 350.4245759062.

Adding to 43031221 its reverse (12213034), we get a palindrome (55244255).

The spelling of 43031221 in words is "forty-three million, thirty-one thousand, two hundred twenty-one".