220400305 has 8 divisors (see below), whose sum is σ = 271628712. Its totient is φ = 171554688.

The previous prime is 220400293. The next prime is 220400309. The reversal of 220400305 is 503004022.

It can be written as a sum of positive squares in 4 ways, for example, as 28633201 + 191767104 = 5351^2 + 13848^2 .

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 220400305 - 2⁷ = 220400177 is a prime.

It is a super-3 number, since 3×220400305³ (a number of 26 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (220400309) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 595492 + ... + 595861.

It is an arithmetic number, because the mean of its divisors is an integer number (33953589).

Almost surely, 2^220400305 is an apocalyptic number.

It is an amenable number.

220400305 is a deficient number, since it is larger than the sum of its proper divisors (51228407).

220400305 is a wasteful number, since it uses less digits than its factorization.

220400305 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1191395.

The product of its (nonzero) digits is 240, while the sum is 16.

The square root of 220400305 is about 14845.8851201267. The cubic root of 220400305 is about 604.0469981192.

Adding to 220400305 its reverse (503004022), we get a palindrome (723404327).

The spelling of 220400305 in words is "two hundred twenty million, four hundred thousand, three hundred five".