1281806 has 8 divisors (see below), whose sum is σ = 1928640. Its totient is φ = 638928.

The previous prime is 1281803. The next prime is 1281809. The reversal of 1281806 is 6081821.

It is an interprime number because it is at equal distance from previous prime (1281803) and next prime (1281809).

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1281803) 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, 35 + ... + 1601.

It is an arithmetic number, because the mean of its divisors is an integer number (241080).

2^1281806 is an apocalyptic number.

1281806 is a deficient number, since it is larger than the sum of its proper divisors (646834).

1281806 is a wasteful number, since it uses less digits than its factorization.

1281806 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1978.

The product of its (nonzero) digits is 768, while the sum is 26.

The square root of 1281806 is about 1132.1687153424. The cubic root of 1281806 is about 108.6277456475.

It can be divided in two parts, 12 and 81806, that added together give a palindrome (81818).

The spelling of 1281806 in words is "one million, two hundred eighty-one thousand, eight hundred six".