1328281 has 4 divisors (see below), whose sum is σ = 1332864. Its totient is φ = 1323700.

The previous prime is 1328279. The next prime is 1328297. The reversal of 1328281 is 1828231.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1328281 - 2¹ = 1328279 is a prime.

It is a super-2 number, since 2×1328281² = 3528660829922, which contains 22 as substring.

It is an Ulam number.

It is a Duffinian number.

It is a plaindrome in base 16.

It is not an unprimeable number, because it can be changed into a prime (1328231) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1825 + ... + 2446.

It is an arithmetic number, because the mean of its divisors is an integer number (333216).

2^1328281 is an apocalyptic number.

It is an amenable number.

1328281 is a deficient number, since it is larger than the sum of its proper divisors (4583).

1328281 is an equidigital number, since it uses as much as digits as its factorization.

1328281 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4582.

The product of its digits is 768, while the sum is 25.

The square root of 1328281 is about 1152.5107374771. The cubic root of 1328281 is about 109.9250453558.

It can be divided in two parts, 13 and 28281, that multiplied together give a triangular number (367653 = T₈₅₇).

The spelling of 1328281 in words is "one million, three hundred twenty-eight thousand, two hundred eighty-one".