221345455 has 8 divisors (see below), whose sum is σ = 268193952. Its totient is φ = 175356768.

The previous prime is 221345441. The next prime is 221345461. The reversal of 221345455 is 554543122.

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 221345455 - 2¹⁵ = 221312687 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 214384 + ... + 215413.

It is an arithmetic number, because the mean of its divisors is an integer number (33524244).

Almost surely, 2^221345455 is an apocalyptic number.

221345455 is a deficient number, since it is larger than the sum of its proper divisors (46848497).

221345455 is a wasteful number, since it uses less digits than its factorization.

221345455 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 429905.

The product of its digits is 24000, while the sum is 31.

The square root of 221345455 is about 14877.6831193570. The cubic root of 221345455 is about 604.9092184439.

Adding to 221345455 its reverse (554543122), we get a palindrome (775888577).

The spelling of 221345455 in words is "two hundred twenty-one million, three hundred forty-five thousand, four hundred fifty-five".