1215278247 has 16 divisors (see below), whose sum is σ = 1712016000. Its totient is φ = 764681184.

The previous prime is 1215278237. The next prime is 1215278257. The reversal of 1215278247 is 7428725121.

It is an interprime number because it is at equal distance from previous prime (1215278237) and next prime (1215278257).

It is not a de Polignac number, because 1215278247 - 2¹¹ = 1215276199 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1215278237) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 24297 + ... + 54962.

It is an arithmetic number, because the mean of its divisors is an integer number (107001000).

Almost surely, 2^1215278247 is an apocalyptic number.

1215278247 is a deficient number, since it is larger than the sum of its proper divisors (496737753).

1215278247 is a wasteful number, since it uses less digits than its factorization.

1215278247 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 79550.

The product of its digits is 62720, while the sum is 39.

The square root of 1215278247 is about 34860.8411688531. The cubic root of 1215278247 is about 1067.1494414994.

The spelling of 1215278247 in words is "one billion, two hundred fifteen million, two hundred seventy-eight thousand, two hundred forty-seven".