1287238986 has 64 divisors (see below), whose sum is σ = 3124863360. Its totient is φ = 389537280.

The previous prime is 1287238969. The next prime is 1287239021. The reversal of 1287238986 is 6898327821.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 757690 + ... + 759386.

It is an arithmetic number, because the mean of its divisors is an integer number (48825990).

Almost surely, 2^1287238986 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1287238986, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1562431680).

1287238986 is an abundant number, since it is smaller than the sum of its proper divisors (1837624374).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1287238986 is a wasteful number, since it uses less digits than its factorization.

1287238986 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2996 (or 2990 counting only the distinct ones).

The product of its digits is 2322432, while the sum is 54.

The square root of 1287238986 is about 35878.1129102410. The cubic root of 1287238986 is about 1087.8100366920.

The spelling of 1287238986 in words is "one billion, two hundred eighty-seven million, two hundred thirty-eight thousand, nine hundred eighty-six".