221420347 has 2 divisors, whose sum is σ = 221420348. Its totient is φ = 221420346.

The previous prime is 221420323. The next prime is 221420363. The reversal of 221420347 is 743024122.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 221420347 - 2¹¹ = 221418299 is a prime.

It is not a weakly prime, because it can be changed into another prime (221220347) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110710173 + 110710174.

It is an arithmetic number, because the mean of its divisors is an integer number (110710174).

Almost surely, 2^221420347 is an apocalyptic number.

221420347 is a deficient number, since it is larger than the sum of its proper divisors (1).

221420347 is an equidigital number, since it uses as much as digits as its factorization.

221420347 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2688, while the sum is 25.

The square root of 221420347 is about 14880.1998306474. The cubic root of 221420347 is about 604.9774342151.

Adding to 221420347 its reverse (743024122), we get a palindrome (964444469).

The spelling of 221420347 in words is "two hundred twenty-one million, four hundred twenty thousand, three hundred forty-seven".