1311221120544 has 72 divisors (see below), whose sum is σ = 3741511531212. Its totient is φ = 435581959680.

The previous prime is 1311221120509. The next prime is 1311221120557. The reversal of 1311221120544 is 4450211221131.

1311221120544 is a `hidden beast` number, since 1 + 3 + 1 + 1 + 2 + 2 + 112 + 0 + 544 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 1181612480400 + 129608640144 = 1087020^2 + 360012^2 .

It is a tau number, because it is divible by the number of its divisors (72).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 7684987 + ... + 7853754.

Almost surely, 2^{1311221120544} is an apocalyptic number.

It is an amenable number.

1311221120544 is an abundant number, since it is smaller than the sum of its proper divisors (2430290410668).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1311221120544 is a wasteful number, since it uses less digits than its factorization.

1311221120544 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15539050 (or 15539039 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 27.

Adding to 1311221120544 its reverse (4450211221131), we get a palindrome (5761432341675).

The spelling of 1311221120544 in words is "one trillion, three hundred eleven billion, two hundred twenty-one million, one hundred twenty thousand, five hundred forty-four".