1242055701891 has 12 divisors (see below), whose sum is σ = 1860527883032. Its totient is φ = 828037134432.

The previous prime is 1242055701847. The next prime is 1242055701919. The reversal of 1242055701891 is 1981075502421.

1242055701891 is a `hidden beast` number, since 1 + 2 + 4 + 2 + 0 + 557 + 0 + 1 + 8 + 91 = 666.

It is not a de Polignac number, because 1242055701891 - 2⁹ = 1242055701379 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1242055702891) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2555669926 + ... + 2555670411.

Almost surely, 2^{1242055701891} is an apocalyptic number.

1242055701891 is a deficient number, since it is larger than the sum of its proper divisors (618472181141).

1242055701891 is an frugal number, since it uses more digits than its factorization.

1242055701891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5111340352 (or 5111340340 counting only the distinct ones).

The product of its (nonzero) digits is 201600, while the sum is 45.

The spelling of 1242055701891 in words is "one trillion, two hundred forty-two billion, fifty-five million, seven hundred one thousand, eight hundred ninety-one".