1287915415 has 4 divisors (see below), whose sum is σ = 1545498504. Its totient is φ = 1030332328.

The previous prime is 1287915413. The next prime is 1287915443. The reversal of 1287915415 is 5145197821.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5145197821 = 149 ⋅34531529.

It is a cyclic number.

It is not a de Polignac number, because 1287915415 - 2¹ = 1287915413 is a prime.

It is a super-2 number, since 2×1287915415² = 3317452232389244450, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1287915413) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 128791537 + ... + 128791546.

It is an arithmetic number, because the mean of its divisors is an integer number (386374626).

Almost surely, 2^1287915415 is an apocalyptic number.

1287915415 is a deficient number, since it is larger than the sum of its proper divisors (257583089).

1287915415 is an equidigital number, since it uses as much as digits as its factorization.

1287915415 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 257583088.

The product of its digits is 100800, while the sum is 43.

The square root of 1287915415 is about 35887.5384360644. The cubic root of 1287915415 is about 1088.0005471338. Note that the first 3 decimals are identical.

The spelling of 1287915415 in words is "one billion, two hundred eighty-seven million, nine hundred fifteen thousand, four hundred fifteen".