1266534400 has 144 divisors (see below), whose sum is σ = 3252330900. Its totient is φ = 488570880.

The previous prime is 1266534389. The next prime is 1266534407. The reversal of 1266534400 is 44356621.

It can be written as a sum of positive squares in 6 ways, for example, as 178062336 + 1088472064 = 13344^2 + 32992^2 .

It is not an unprimeable number, because it can be changed into a prime (1266534407) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1484374 + ... + 1485226.

Almost surely, 2^1266534400 is an apocalyptic number.

1266534400 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 1266534400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1626165450).

1266534400 is an abundant number, since it is smaller than the sum of its proper divisors (1985796500).

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

1266534400 is an equidigital number, since it uses as much as digits as its factorization.

1266534400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 914 (or 889 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 31.

The square root of 1266534400 is about 35588.4026053432. The cubic root of 1266534400 is about 1081.9461935812.

The spelling of 1266534400 in words is "one billion, two hundred sixty-six million, five hundred thirty-four thousand, four hundred".