1287906240 has 112 divisors (see below), whose sum is σ = 4230197280. Its totient is φ = 331591680.

The previous prime is 1287906209. The next prime is 1287906259. The reversal of 1287906240 is 426097821.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4710 + ... + 50970.

Almost surely, 2^1287906240 is an apocalyptic number.

1287906240 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1287906240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2115098640).

1287906240 is an abundant number, since it is smaller than the sum of its proper divisors (2942291040).

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

1287906240 is a wasteful number, since it uses less digits than its factorization.

1287906240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 46310 (or 46300 counting only the distinct ones).

The product of its (nonzero) digits is 48384, while the sum is 39.

The square root of 1287906240 is about 35887.4106059493. The cubic root of 1287906240 is about 1087.9979635198.

The spelling of 1287906240 in words is "one billion, two hundred eighty-seven million, nine hundred six thousand, two hundred forty".