1256681268 has 72 divisors (see below), whose sum is σ = 3323943168. Its totient is φ = 399567168.

The previous prime is 1256681243. The next prime is 1256681281. The reversal of 1256681268 is 8621866521.

1256681268 is a `hidden beast` number, since 1 + 2 + 566 + 81 + 2 + 6 + 8 = 666.

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 326805 + ... + 330627.

Almost surely, 2^1256681268 is an apocalyptic number.

1256681268 is a gapful number since it is divisible by the number (18) 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 1256681268, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1661971584).

1256681268 is an abundant number, since it is smaller than the sum of its proper divisors (2067261900).

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

1256681268 is a wasteful number, since it uses less digits than its factorization.

1256681268 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4253 (or 4248 counting only the distinct ones).

The product of its digits is 276480, while the sum is 45.

The square root of 1256681268 is about 35449.7005347013. The cubic root of 1256681268 is about 1079.1331830725.

The spelling of 1256681268 in words is "one billion, two hundred fifty-six million, six hundred eighty-one thousand, two hundred sixty-eight".