1221123005 has 8 divisors (see below), whose sum is σ = 1551544632. Its totient is φ = 919433728.

The previous prime is 1221122999. The next prime is 1221123023. The reversal of 1221123005 is 5003211221.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 144889369 + 1076233636 = 12037^2 + 32806^2 .

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 1221123005 - 2¹² = 1221118909 is a prime.

It is a super-2 number, since 2×1221123005² = 2982282786680460050, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (17).

It is a Duffinian number.

It is a congruent number.

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 7 ways as a sum of consecutive naturals, for example, 7182992 + ... + 7183161.

It is an arithmetic number, because the mean of its divisors is an integer number (193943079).

Almost surely, 2^1221123005 is an apocalyptic number.

It is an amenable number.

1221123005 is a deficient number, since it is larger than the sum of its proper divisors (330421627).

1221123005 is a wasteful number, since it uses less digits than its factorization.

1221123005 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14366175.

The product of its (nonzero) digits is 120, while the sum is 17.

The square root of 1221123005 is about 34944.5704652382. The cubic root of 1221123005 is about 1068.8574886818.

Adding to 1221123005 its reverse (5003211221), we get a palindrome (6224334226).

The spelling of 1221123005 in words is "one billion, two hundred twenty-one million, one hundred twenty-three thousand, five".