1320668281 has 3 divisors (see below), whose sum is σ = 1320704623. Its totient is φ = 1320631940.

The previous prime is 1320668267. The next prime is 1320668287. The reversal of 1320668281 is 1828660231.

It is a happy number.

The square root of 1320668281 is 36341.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in only one way, i.e., 1030987881 + 289680400 = 32109^2 + 17020^2 .

It is not a de Polignac number, because 1320668281 - 2¹⁷ = 1320537209 is a prime.

It is a super-2 number, since 2×1320668281² = 3488329416878989922, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1320668281.

It is not an unprimeable number, because it can be changed into a prime (1320668287) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 18171 + ... + 54511.

Almost surely, 2^1320668281 is an apocalyptic number.

1320668281 is the 36341-st square number.

1320668281 is the 18171-st centered octagonal number.

It is an amenable number.

1320668281 is a deficient number, since it is larger than the sum of its proper divisors (36342).

1320668281 is an frugal number, since it uses more digits than its factorization.

1320668281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 72682 (or 36341 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 37.

The cubic root of 1320668281 is about 1097.1464000632.

The spelling of 1320668281 in words is "one billion, three hundred twenty million, six hundred sixty-eight thousand, two hundred eighty-one".