1287029940 has 96 divisors (see below), whose sum is σ = 4130832384. Its totient is φ = 293297280.

The previous prime is 1287029873. The next prime is 1287029963. The reversal of 1287029940 is 499207821.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a junction number, because it is equal to n+sod(n) for n = 1287029892 and 1287029901.

It is a congruent number.

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, 141325 + ... + 150155.

It is an arithmetic number, because the mean of its divisors is an integer number (43029504).

Almost surely, 2^1287029940 is an apocalyptic number.

1287029940 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 1287029940, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2065416192).

1287029940 is an abundant number, since it is smaller than the sum of its proper divisors (2843802444).

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

1287029940 is a wasteful number, since it uses less digits than its factorization.

1287029940 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9197 (or 9195 counting only the distinct ones).

The product of its (nonzero) digits is 72576, while the sum is 42.

The square root of 1287029940 is about 35875.1995116403. The cubic root of 1287029940 is about 1087.7511471746.

The spelling of 1287029940 in words is "one billion, two hundred eighty-seven million, twenty-nine thousand, nine hundred forty".