1243666680261 has 8 divisors (see below), whose sum is σ = 1658228948640. Its totient is φ = 829107766032.

The previous prime is 1243666680241. The next prime is 1243666680301. The reversal of 1243666680261 is 1620866663421.

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

It is not a de Polignac number, because 1243666680261 - 2⁷ = 1243666680133 is a prime.

It is a Smith number, since the sum of its digits (51) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1243666680241) 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 7 ways as a sum of consecutive naturals, for example, 216130 + ... + 1591868.

It is an arithmetic number, because the mean of its divisors is an integer number (207278618580).

Almost surely, 2^{1243666680261} is an apocalyptic number.

It is an amenable number.

1243666680261 is a deficient number, since it is larger than the sum of its proper divisors (414562268379).

1243666680261 is a wasteful number, since it uses less digits than its factorization.

1243666680261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1677075.

The product of its (nonzero) digits is 2985984, while the sum is 51.

The spelling of 1243666680261 in words is "one trillion, two hundred forty-three billion, six hundred sixty-six million, six hundred eighty thousand, two hundred sixty-one".