1266236544 has 64 divisors (see below), whose sum is σ = 3369990240. Its totient is φ = 421257216.

The previous prime is 1266236519. The next prime is 1266236561. The reversal of 1266236544 is 4456326621.

It is a tau number, because it is divible by the number of its divisors (64).

It is a super-2 number, since 2×1266236544² = 3206709970722127872, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 213264 + ... + 219120.

Almost surely, 2^1266236544 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1266236544, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1684995120).

1266236544 is an abundant number, since it is smaller than the sum of its proper divisors (2103753696).

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

1266236544 is an equidigital number, since it uses as much as digits as its factorization.

1266236544 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6437 (or 6425 counting only the distinct ones).

The product of its digits is 207360, while the sum is 39.

The square root of 1266236544 is about 35584.2176252338. The cubic root of 1266236544 is about 1081.8613717158.

The spelling of 1266236544 in words is "one billion, two hundred sixty-six million, two hundred thirty-six thousand, five hundred forty-four".