1242105121511 has 4 divisors (see below), whose sum is σ = 1242109472400. Its totient is φ = 1242100770624.

The previous prime is 1242105121507. The next prime is 1242105121519. The reversal of 1242105121511 is 1151215012421.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1242105121511 - 2² = 1242105121507 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1242105121519) 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 3 ways as a sum of consecutive naturals, for example, 1714691 + ... + 2329028.

It is an arithmetic number, because the mean of its divisors is an integer number (310527368100).

Almost surely, 2^{1242105121511} is an apocalyptic number.

1242105121511 is a deficient number, since it is larger than the sum of its proper divisors (4350889).

1242105121511 is an equidigital number, since it uses as much as digits as its factorization.

1242105121511 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4350888.

The product of its (nonzero) digits is 800, while the sum is 26.

The spelling of 1242105121511 in words is "one trillion, two hundred forty-two billion, one hundred five million, one hundred twenty-one thousand, five hundred eleven".