1311242121505 has 8 divisors (see below), whose sum is σ = 1591170215400. Its totient is φ = 1037207250816.

The previous prime is 1311242121499. The next prime is 1311242121557. The reversal of 1311242121505 is 5051212421131.

It can be written as a sum of positive squares in 4 ways, for example, as 210339642384 + 1100902479121 = 458628^2 + 1049239^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1311242121505 - 2⁵ = 1311242121473 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1473305310 + ... + 1473306199.

It is an arithmetic number, because the mean of its divisors is an integer number (198896276925).

Almost surely, 2^{1311242121505} is an apocalyptic number.

It is an amenable number.

1311242121505 is a deficient number, since it is larger than the sum of its proper divisors (279928093895).

1311242121505 is an equidigital number, since it uses as much as digits as its factorization.

1311242121505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2946611603.

The product of its (nonzero) digits is 2400, while the sum is 28.

Adding to 1311242121505 its reverse (5051212421131), we get a palindrome (6362454542636).

The spelling of 1311242121505 in words is "one trillion, three hundred eleven billion, two hundred forty-two million, one hundred twenty-one thousand, five hundred five".