1221222305 has 4 divisors (see below), whose sum is σ = 1465466772. Its totient is φ = 976977840.

The previous prime is 1221222287. The next prime is 1221222341. The reversal of 1221222305 is 5032221221.

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 922762129 + 298460176 = 30377^2 + 17276^2 .

It is not a de Polignac number, because 1221222305 - 2¹⁸ = 1220960161 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 122122226 + ... + 122122235.

It is an arithmetic number, because the mean of its divisors is an integer number (366366693).

Almost surely, 2^1221222305 is an apocalyptic number.

It is an amenable number.

1221222305 is a deficient number, since it is larger than the sum of its proper divisors (244244467).

1221222305 is an equidigital number, since it uses as much as digits as its factorization.

1221222305 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 244244466.

The product of its (nonzero) digits is 480, while the sum is 20.

The square root of 1221222305 is about 34945.9912579397. The cubic root of 1221222305 is about 1068.8864605575.

Adding to 1221222305 its reverse (5032221221), we get a palindrome (6253443526).

The spelling of 1221222305 in words is "one billion, two hundred twenty-one million, two hundred twenty-two thousand, three hundred five".