1266378766263 has 32 divisors (see below), whose sum is σ = 2020819046400. Its totient is φ = 779161245408.

The previous prime is 1266378766253. The next prime is 1266378766267. The reversal of 1266378766263 is 3626678736621.

1266378766263 is a `hidden beast` number, since 1 + 266 + 37 + 87 + 6 + 6 + 263 = 666.

It is not a de Polignac number, because 1266378766263 - 2⁶ = 1266378766199 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1266378766263.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1266378766267) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1511206 + ... + 2194652.

It is an arithmetic number, because the mean of its divisors is an integer number (63150595200).

Almost surely, 2^{1266378766263} is an apocalyptic number.

1266378766263 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

1266378766263 is a deficient number, since it is larger than the sum of its proper divisors (754440280137).

1266378766263 is a wasteful number, since it uses less digits than its factorization.

1266378766263 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 688748 (or 688742 counting only the distinct ones).

The product of its digits is 109734912, while the sum is 63.

The spelling of 1266378766263 in words is "one trillion, two hundred sixty-six billion, three hundred seventy-eight million, seven hundred sixty-six thousand, two hundred sixty-three".