1212220305 has 24 divisors (see below), whose sum is σ = 2106068328. Its totient is φ = 645014016.

The previous prime is 1212220301. The next prime is 1212220333. The reversal of 1212220305 is 5030222121.

It can be written as a sum of positive squares in 4 ways, for example, as 44836416 + 1167383889 = 6696^2 + 34167^2 .

It is not a de Polignac number, because 1212220305 - 2² = 1212220301 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1212220301) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 11622 + ... + 50591.

It is an arithmetic number, because the mean of its divisors is an integer number (87752847).

Almost surely, 2^1212220305 is an apocalyptic number.

1212220305 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1212220305 is a deficient number, since it is larger than the sum of its proper divisors (893848023).

1212220305 is a wasteful number, since it uses less digits than its factorization.

1212220305 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 62657 (or 62654 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

The square root of 1212220305 is about 34816.9542751804. The cubic root of 1212220305 is about 1066.2536186666.

Adding to 1212220305 its reverse (5030222121), we get a palindrome (6242442426).

The spelling of 1212220305 in words is "one billion, two hundred twelve million, two hundred twenty thousand, three hundred five".