1213021105 has 8 divisors (see below), whose sum is σ = 1460219112. Its totient is φ = 967354368.

The previous prime is 1213021091. The next prime is 1213021157. The reversal of 1213021105 is 5011203121.

It can be written as a sum of positive squares in 4 ways, for example, as 10942864 + 1202078241 = 3308^2 + 34671^2 .

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 1213021105 - 2²³ = 1204632497 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 381072 + ... + 384241.

It is an arithmetic number, because the mean of its divisors is an integer number (182527389).

Almost surely, 2^1213021105 is an apocalyptic number.

It is an amenable number.

1213021105 is a deficient number, since it is larger than the sum of its proper divisors (247198007).

1213021105 is an equidigital number, since it uses as much as digits as its factorization.

1213021105 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 765635.

The product of its (nonzero) digits is 60, while the sum is 16.

The square root of 1213021105 is about 34828.4525208916. The cubic root of 1213021105 is about 1066.4883581614.

Adding to 1213021105 its reverse (5011203121), we get a palindrome (6224224226).

The spelling of 1213021105 in words is "one billion, two hundred thirteen million, twenty-one thousand, one hundred five".