1287980 has 12 divisors (see below), whose sum is σ = 2704800. Its totient is φ = 515184.

The previous prime is 1287973. The next prime is 1287983. The reversal of 1287980 is 897821.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 1287980.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1287983) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 32180 + ... + 32219.

It is an arithmetic number, because the mean of its divisors is an integer number (225400).

2^1287980 is an apocalyptic number.

1287980 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1287980 is an abundant number, since it is smaller than the sum of its proper divisors (1416820).

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

1287980 is a wasteful number, since it uses less digits than its factorization.

1287980 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 64408 (or 64406 counting only the distinct ones).

The product of its (nonzero) digits is 8064, while the sum is 35.

The square root of 1287980 is about 1134.8920653525. The cubic root of 1287980 is about 108.8018733458.

The spelling of 1287980 in words is "one million, two hundred eighty-seven thousand, nine hundred eighty".