1211242505 has 8 divisors (see below), whose sum is σ = 1585626624. Its totient is φ = 880903600.

The previous prime is 1211242481. The next prime is 1211242519. The reversal of 1211242505 is 5052421121.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1211242505 - 2⁶ = 1211242441 is a prime.

It is a Duffinian number.

It is a Curzon 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, 11011241 + ... + 11011350.

It is an arithmetic number, because the mean of its divisors is an integer number (198203328).

Almost surely, 2^1211242505 is an apocalyptic number.

It is an amenable number.

1211242505 is a deficient number, since it is larger than the sum of its proper divisors (374384119).

1211242505 is a wasteful number, since it uses less digits than its factorization.

1211242505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22022607.

The product of its (nonzero) digits is 800, while the sum is 23.

The square root of 1211242505 is about 34802.9094329770. The cubic root of 1211242505 is about 1065.9668547200.

Adding to 1211242505 its reverse (5052421121), we get a palindrome (6263663626).

The spelling of 1211242505 in words is "one billion, two hundred eleven million, two hundred forty-two thousand, five hundred five".