221814409 has 4 divisors (see below), whose sum is σ = 221856516.
Its totient is φ = 221772304.
The previous prime is 221814407. The next prime is 221814427. The reversal of 221814409 is 904418122.
221814409 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.
It is a semiprime because it is the product of two primes.
It can be written as a sum of positive squares in 2 ways, for example, as 60016009 + 161798400 = 7747^2 + 12720^2
It is a cyclic number.
It is not a de Polignac number, because 221814409 - 21 = 221814407 is a prime.
It is a Duffinian number.
It is not an unprimeable number, because it can be changed into a prime (221814407) 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, 11794 + ... + 24139.
It is an arithmetic number, because the mean of its divisors is an integer number (55464129).
It is a 5268-hyperperfect number.
Almost surely, 2221814409 is an apocalyptic number.
It is an amenable number.
221814409 is a deficient number, since it is larger than the sum of its proper divisors (42107).
221814409 is an equidigital number, since it uses as much as digits as its factorization.
221814409 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 42106.
The product of its (nonzero) digits is 4608, while the sum is 31.
The square root of 221814409 is about 14893.4350973844.
The cubic root of 221814409 is about 605.3361144877.
The spelling of 221814409 in words is "two hundred twenty-one million, eight hundred fourteen thousand, four hundred nine".