1266127260221 has 4 divisors (see below), whose sum is σ = 1266141430272. Its totient is φ = 1266113090172.

The previous prime is 1266127260187. The next prime is 1266127260289. The reversal of 1266127260221 is 1220627216621.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1266127260221 - 2¹⁸ = 1266126998077 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1266127260721) 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, 6950141 + ... + 7129986.

It is an arithmetic number, because the mean of its divisors is an integer number (316535357568).

Almost surely, 2^{1266127260221} is an apocalyptic number.

It is an amenable number.

1266127260221 is a deficient number, since it is larger than the sum of its proper divisors (14170051).

1266127260221 is an equidigital number, since it uses as much as digits as its factorization.

1266127260221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14170050.

The product of its (nonzero) digits is 48384, while the sum is 38.

The spelling of 1266127260221 in words is "one trillion, two hundred sixty-six billion, one hundred twenty-seven million, two hundred sixty thousand, two hundred twenty-one".