1328781 has 8 divisors (see below), whose sum is σ = 1819744. Its totient is φ = 861840.

The previous prime is 1328777. The next prime is 1328783. The reversal of 1328781 is 1878231.

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 1328781 - 2² = 1328777 is a prime.

It is a super-2 number, since 2×1328781² = 3531317891922, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a plaindrome in base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1328783) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5875 + ... + 6096.

It is an arithmetic number, because the mean of its divisors is an integer number (227468).

2^1328781 is an apocalyptic number.

It is an amenable number.

1328781 is a deficient number, since it is larger than the sum of its proper divisors (490963).

1328781 is a wasteful number, since it uses less digits than its factorization.

1328781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12011.

The product of its digits is 2688, while the sum is 30.

The square root of 1328781 is about 1152.7276347863. The cubic root of 1328781 is about 109.9388365209.

The spelling of 1328781 in words is "one million, three hundred twenty-eight thousand, seven hundred eighty-one".