1266481440 has 576 divisors, whose sum is σ = 5350302720. Its totient is φ = 278691840.

The previous prime is 1266481429. The next prime is 1266481441. The reversal of 1266481440 is 441846621.

It is a happy number.

1266481440 is a `hidden beast` number, since 1 + 2 + 6 + 648 + 1 + 4 + 4 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 1266481395 and 1266481404.

It is not an unprimeable number, because it can be changed into a prime (1266481441) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 6561984 + ... + 6562176.

It is an arithmetic number, because the mean of its divisors is an integer number (9288720).

Almost surely, 2^1266481440 is an apocalyptic number.

1266481440 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 1266481440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2675151360).

1266481440 is an abundant number, since it is smaller than the sum of its proper divisors (4083821280).

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

1266481440 is a wasteful number, since it uses less digits than its factorization.

1266481440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 262 (or 241 counting only the distinct ones).

The product of its (nonzero) digits is 36864, while the sum is 36.

The square root of 1266481440 is about 35587.6585349472. The cubic root of 1266481440 is about 1081.9311128830.

The spelling of 1266481440 in words is "one billion, two hundred sixty-six million, four hundred eighty-one thousand, four hundred forty".