1287881 has 8 divisors (see below), whose sum is σ = 1479744. Its totient is φ = 1098000.

The previous prime is 1287857. The next prime is 1287883. The reversal of 1287881 is 1887821.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1287881 - 2⁶ = 1287817 is a prime.

It is a super-2 number, since 2×1287881² = 3317274940322, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1287883) 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 7 ways as a sum of consecutive naturals, for example, 1391 + ... + 2123.

It is an arithmetic number, because the mean of its divisors is an integer number (184968).

2^1287881 is an apocalyptic number.

It is an amenable number.

1287881 is a deficient number, since it is larger than the sum of its proper divisors (191863).

1287881 is an equidigital number, since it uses as much as digits as its factorization.

1287881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 991.

The product of its digits is 7168, while the sum is 35.

The square root of 1287881 is about 1134.8484480317. The cubic root of 1287881 is about 108.7990856054.

The spelling of 1287881 in words is "one million, two hundred eighty-seven thousand, eight hundred eighty-one".