221253605 has 8 divisors (see below), whose sum is σ = 268242072. Its totient is φ = 175177728.

The previous prime is 221253601. The next prime is 221253607. The reversal of 221253605 is 506352122.

221253605 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 1295044 + 219958561 = 1138^2 + 14831^2 .

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 221253605 - 2² = 221253601 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221253601) 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, 227612 + ... + 228581.

It is an arithmetic number, because the mean of its divisors is an integer number (33530259).

Almost surely, 2^221253605 is an apocalyptic number.

It is an amenable number.

221253605 is a deficient number, since it is larger than the sum of its proper divisors (46988467).

221253605 is an equidigital number, since it uses as much as digits as its factorization.

221253605 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 456295.

The product of its (nonzero) digits is 3600, while the sum is 26.

The square root of 221253605 is about 14874.5959608992. The cubic root of 221253605 is about 604.8255353783.

The spelling of 221253605 in words is "two hundred twenty-one million, two hundred fifty-three thousand, six hundred five".