1287156860 has 48 divisors (see below), whose sum is σ = 2973190752. Its totient is φ = 468047360.

The previous prime is 1287156847. The next prime is 1287156877. The reversal of 1287156860 is 686517821.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (44).

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, 2444 + ... + 50796.

It is an arithmetic number, because the mean of its divisors is an integer number (61941474).

Almost surely, 2^1287156860 is an apocalyptic number.

1287156860 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 1287156860, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1486595376).

1287156860 is an abundant number, since it is smaller than the sum of its proper divisors (1686033892).

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

1287156860 is a wasteful number, since it uses less digits than its factorization.

1287156860 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 48395 (or 48371 counting only the distinct ones).

The product of its (nonzero) digits is 161280, while the sum is 44.

The square root of 1287156860 is about 35876.9683780556. The cubic root of 1287156860 is about 1087.7869020636.

The spelling of 1287156860 in words is "one billion, two hundred eighty-seven million, one hundred fifty-six thousand, eight hundred sixty".