1256133312 has 224 divisors, whose sum is σ = 4262323200. Its totient is φ = 355332096.

The previous prime is 1256133311. The next prime is 1256133317. The reversal of 1256133312 is 2133316521.

1256133312 is a `hidden beast` number, since 1 + 2 + 5 + 613 + 33 + 12 = 666.

It is a tau number, because it is divible by the number of its divisors (224).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1256133311) 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, 1366389 + ... + 1367307.

Almost surely, 2^1256133312 is an apocalyptic number.

1256133312 is a gapful number since it is divisible by the number (12) 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 1256133312, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2131161600).

1256133312 is an abundant number, since it is smaller than the sum of its proper divisors (3006189888).

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

1256133312 is a wasteful number, since it uses less digits than its factorization.

1256133312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1060 (or 1044 counting only the distinct ones).

The product of its digits is 3240, while the sum is 27.

The square root of 1256133312 is about 35441.9710512833. The cubic root of 1256133312 is about 1078.9763139487.

Adding to 1256133312 its reverse (2133316521), we get a palindrome (3389449833).

The spelling of 1256133312 in words is "one billion, two hundred fifty-six million, one hundred thirty-three thousand, three hundred twelve".