1221268609 has 6 divisors (see below), whose sum is σ = 1342386290. Its totient is φ = 1110244080.

The previous prime is 1221268603. The next prime is 1221268649. The reversal of 1221268609 is 9068621221.

It can be written as a sum of positive squares in only one way, i.e., 1069486209 + 151782400 = 32703^2 + 12320^2 .

It is not a de Polignac number, because 1221268609 - 2⁵ = 1221268577 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1221268603) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 5046444 + ... + 5046685.

Almost surely, 2^1221268609 is an apocalyptic number.

It is an amenable number.

1221268609 is a deficient number, since it is larger than the sum of its proper divisors (121117681).

1221268609 is a wasteful number, since it uses less digits than its factorization.

1221268609 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10093151 (or 10093140 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 37.

The square root of 1221268609 is about 34946.6537596949. The cubic root of 1221268609 is about 1068.8999697258.

The spelling of 1221268609 in words is "one billion, two hundred twenty-one million, two hundred sixty-eight thousand, six hundred nine".