1266566427381 has 16 divisors (see below), whose sum is σ = 1788121652544. Its totient is φ = 794695958784.

The previous prime is 1266566427377. The next prime is 1266566427389. The reversal of 1266566427381 is 1837246656621.

It is not a de Polignac number, because 1266566427381 - 2² = 1266566427377 is a prime.

It is a super-2 number, since 2×1266566427381² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1266566427389) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3986850 + ... + 4292796.

It is an arithmetic number, because the mean of its divisors is an integer number (111757603284).

Almost surely, 2^{1266566427381} is an apocalyptic number.

It is an amenable number.

1266566427381 is a deficient number, since it is larger than the sum of its proper divisors (521555225163).

1266566427381 is a wasteful number, since it uses less digits than its factorization.

1266566427381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 387140.

The product of its digits is 17418240, while the sum is 57.

The spelling of 1266566427381 in words is "one trillion, two hundred sixty-six billion, five hundred sixty-six million, four hundred twenty-seven thousand, three hundred eighty-one".