1211215045 has 4 divisors (see below), whose sum is σ = 1453458060. Its totient is φ = 968972032.

The previous prime is 1211215009. The next prime is 1211215063. The reversal of 1211215045 is 5405121121.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 919181124 + 292033921 = 30318^2 + 17089^2 .

It is a cyclic number.

It is not a de Polignac number, because 1211215045 - 2¹³ = 1211206853 is a prime.

It is a congruent 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 3 ways as a sum of consecutive naturals, for example, 121121500 + ... + 121121509.

It is an arithmetic number, because the mean of its divisors is an integer number (363364515).

Almost surely, 2^1211215045 is an apocalyptic number.

It is an amenable number.

1211215045 is a deficient number, since it is larger than the sum of its proper divisors (242243015).

1211215045 is an equidigital number, since it uses as much as digits as its factorization.

1211215045 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 242243014.

The product of its (nonzero) digits is 400, while the sum is 22.

The square root of 1211215045 is about 34802.5149234937. The cubic root of 1211215045 is about 1065.9587991708.

Adding to 1211215045 its reverse (5405121121), we get a palindrome (6616336166).

The spelling of 1211215045 in words is "one billion, two hundred eleven million, two hundred fifteen thousand, forty-five".