1266287564640 has 768 divisors, whose sum is σ = 4731839078400. Its totient is φ = 284497920000.

The previous prime is 1266287564611. The next prime is 1266287564657. The reversal of 1266287564640 is 464657826621.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 4506361300 + ... + 4506361580.

It is an arithmetic number, because the mean of its divisors is an integer number (6161248800).

Almost surely, 2^{1266287564640} is an apocalyptic number.

1266287564640 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 1266287564640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2365919539200).

1266287564640 is an abundant number, since it is smaller than the sum of its proper divisors (3465551513760).

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

1266287564640 is a wasteful number, since it uses less digits than its factorization.

1266287564640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 692 (or 670 counting only the distinct ones).

The product of its (nonzero) digits is 23224320, while the sum is 57.

The spelling of 1266287564640 in words is "one trillion, two hundred sixty-six billion, two hundred eighty-seven million, five hundred sixty-four thousand, six hundred forty".