1287243845 has 16 divisors (see below), whose sum is σ = 1616993280. Its totient is φ = 982531200.

The previous prime is 1287243809. The next prime is 1287243847. The reversal of 1287243845 is 5483427821.

It is not a de Polignac number, because 1287243845 - 2⁶ = 1287243781 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 1287243796 and 1287243805.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1287243847) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 47480 + ... + 69489.

It is an arithmetic number, because the mean of its divisors is an integer number (101062080).

Almost surely, 2^1287243845 is an apocalyptic number.

It is an amenable number.

1287243845 is a deficient number, since it is larger than the sum of its proper divisors (329749435).

1287243845 is a wasteful number, since it uses less digits than its factorization.

1287243845 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 117076.

The product of its digits is 430080, while the sum is 44.

The square root of 1287243845 is about 35878.1806255557. The cubic root of 1287243845 is about 1087.8114054258.

The spelling of 1287243845 in words is "one billion, two hundred eighty-seven million, two hundred forty-three thousand, eight hundred forty-five".