1221253105 has 16 divisors (see below), whose sum is σ = 1516458240. Its totient is φ = 943544448.

The previous prime is 1221253069. The next prime is 1221253127. The reversal of 1221253105 is 5013521221.

It is a cyclic number.

It is not a de Polignac number, because 1221253105 - 2²⁷ = 1087035377 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12777 + ... + 51046.

It is an arithmetic number, because the mean of its divisors is an integer number (94778640).

Almost surely, 2^1221253105 is an apocalyptic number.

It is an amenable number.

1221253105 is a deficient number, since it is larger than the sum of its proper divisors (295205135).

1221253105 is an equidigital number, since it uses as much as digits as its factorization.

1221253105 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 63960.

The product of its (nonzero) digits is 600, while the sum is 22.

The square root of 1221253105 is about 34946.4319351776. The cubic root of 1221253105 is about 1068.8954464798.

Adding to 1221253105 its reverse (5013521221), we get a palindrome (6234774326).

The spelling of 1221253105 in words is "one billion, two hundred twenty-one million, two hundred fifty-three thousand, one hundred five".