221420443 has 2 divisors, whose sum is σ = 221420444. Its totient is φ = 221420442.

The previous prime is 221420417. The next prime is 221420453. The reversal of 221420443 is 344024122.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 221420443 - 2⁵ = 221420411 is a prime.

It is not a weakly prime, because it can be changed into another prime (221420453) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110710221 + 110710222.

It is an arithmetic number, because the mean of its divisors is an integer number (110710222).

Almost surely, 2^221420443 is an apocalyptic number.

221420443 is a deficient number, since it is larger than the sum of its proper divisors (1).

221420443 is an equidigital number, since it uses as much as digits as its factorization.

221420443 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1536, while the sum is 22.

The square root of 221420443 is about 14880.2030564102. The cubic root of 221420443 is about 604.9775216474.

Adding to 221420443 its reverse (344024122), we get a palindrome (565444565).

The spelling of 221420443 in words is "two hundred twenty-one million, four hundred twenty thousand, four hundred forty-three".