1266726660 has 96 divisors (see below), whose sum is σ = 3623380992. Its totient is φ = 330577920.

The previous prime is 1266726631. The next prime is 1266726667. The reversal of 1266726660 is 666276621.

It is not an unprimeable number, because it can be changed into a prime (1266726667) 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, 599005 + ... + 601115.

It is an arithmetic number, because the mean of its divisors is an integer number (37743552).

Almost surely, 2^1266726660 is an apocalyptic number.

1266726660 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1266726660, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1811690496).

1266726660 is an abundant number, since it is smaller than the sum of its proper divisors (2356654332).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1266726660 is a wasteful number, since it uses less digits than its factorization.

1266726660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2333 (or 2331 counting only the distinct ones).

The product of its (nonzero) digits is 217728, while the sum is 42.

The square root of 1266726660 is about 35591.1036636966. The cubic root of 1266726660 is about 1082.0009373109. Note that the first 3 decimals are identical.

The spelling of 1266726660 in words is "one billion, two hundred sixty-six million, seven hundred twenty-six thousand, six hundred sixty".