1215738049 has 4 divisors (see below), whose sum is σ = 1241604864. Its totient is φ = 1189871236.

The previous prime is 1215738037. The next prime is 1215738053. The reversal of 1215738049 is 9408375121.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 9408375121 = 33083 ⋅284387.

It is a cyclic number.

It is not a de Polignac number, because 1215738049 - 2⁷ = 1215737921 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1215738019) by changing a digit.

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, 12933337 + ... + 12933430.

It is an arithmetic number, because the mean of its divisors is an integer number (310401216).

Almost surely, 2^1215738049 is an apocalyptic number.

It is an amenable number.

1215738049 is a deficient number, since it is larger than the sum of its proper divisors (25866815).

1215738049 is an equidigital number, since it uses as much as digits as its factorization.

1215738049 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25866814.

The product of its (nonzero) digits is 60480, while the sum is 40.

The square root of 1215738049 is about 34867.4353659686. The cubic root of 1215738049 is about 1067.2840102916.

The spelling of 1215738049 in words is "one billion, two hundred fifteen million, seven hundred thirty-eight thousand, forty-nine".