1280985 has 32 divisors (see below), whose sum is σ = 2211840. Its totient is φ = 631488.

The previous prime is 1280969. The next prime is 1280987. The reversal of 1280985 is 5890821.

It is a happy number.

It is not a de Polignac number, because 1280985 - 2⁴ = 1280969 is a prime.

1280985 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (1280987) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 16176 + ... + 16254.

It is an arithmetic number, because the mean of its divisors is an integer number (69120).

2^1280985 is an apocalyptic number.

1280985 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1280985 is a deficient number, since it is larger than the sum of its proper divisors (930855).

1280985 is a wasteful number, since it uses less digits than its factorization.

1280985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 157.

The product of its (nonzero) digits is 5760, while the sum is 33.

The square root of 1280985 is about 1131.8060787962. The cubic root of 1280985 is about 108.6045485785.

The spelling of 1280985 in words is "one million, two hundred eighty thousand, nine hundred eighty-five".