1289985 has 8 divisors (see below), whose sum is σ = 2064000. Its totient is φ = 687984.

The previous prime is 1289971. The next prime is 1290013. The reversal of 1289985 is 5899821.

It is a happy number.

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

It is not a de Polignac number, because 1289985 - 2⁴ = 1289969 is a prime.

It is a super-2 number, since 2×1289985² = 3328122600450, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 42985 + ... + 43014.

It is an arithmetic number, because the mean of its divisors is an integer number (258000).

2^1289985 is an apocalyptic number.

1289985 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1289985 is a deficient number, since it is larger than the sum of its proper divisors (774015).

1289985 is an equidigital number, since it uses as much as digits as its factorization.

1289985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 86007.

The product of its digits is 51840, while the sum is 42.

The square root of 1289985 is about 1135.7750657591. The cubic root of 1289985 is about 108.8583014106.

The spelling of 1289985 in words is "one million, two hundred eighty-nine thousand, nine hundred eighty-five".