1221011075 has 12 divisors (see below), whose sum is σ = 1538876208. Its totient is φ = 960794400.

The previous prime is 1221011053. The next prime is 1221011081. The reversal of 1221011075 is 5701101221.

It is a happy number.

It is a de Polignac number, because none of the positive numbers 2^k-1221011075 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 398807 + ... + 401856.

It is an arithmetic number, because the mean of its divisors is an integer number (128239684).

Almost surely, 2^1221011075 is an apocalyptic number.

1221011075 is a deficient number, since it is larger than the sum of its proper divisors (317865133).

1221011075 is an equidigital number, since it uses as much as digits as its factorization.

1221011075 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 800734 (or 800729 counting only the distinct ones).

The product of its (nonzero) digits is 140, while the sum is 20.

The square root of 1221011075 is about 34942.9688921820. The cubic root of 1221011075 is about 1068.8248299805.

Adding to 1221011075 its reverse (5701101221), we get a palindrome (6922112296).

The spelling of 1221011075 in words is "one billion, two hundred twenty-one million, eleven thousand, seventy-five".