1320644551249 has 3 divisors (see below), whose sum is σ = 1320645700443. Its totient is φ = 1320643402056.

The previous prime is 1320644551231. The next prime is 1320644551301. The reversal of 1320644551249 is 9421554460231.

The square root of 1320644551249 is 1149193.

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., 1320603180625 + 41370624 = 1149175^2 + 6432^2 .

It is not a de Polignac number, because 1320644551249 - 2⁹ = 1320644550737 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1320644551199 and 1320644551208.

It is not an unprimeable number, because it can be changed into a prime (1320644551229) 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, 574597 + ... + 1723789.

It is an arithmetic number, because the mean of its divisors is an integer number (440215233481).

Almost surely, 2^{1320644551249} is an apocalyptic number.

1320644551249 is the 1149193-rd square number.

1320644551249 is the 574597-th centered octagonal number.

It is an amenable number.

1320644551249 is a deficient number, since it is larger than the sum of its proper divisors (1149194).

1320644551249 is an frugal number, since it uses more digits than its factorization.

1320644551249 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2298386 (or 1149193 counting only the distinct ones).

The product of its (nonzero) digits is 1036800, while the sum is 46.

The spelling of 1320644551249 in words is "one trillion, three hundred twenty billion, six hundred forty-four million, five hundred fifty-one thousand, two hundred forty-nine".