1256317992 has 64 divisors (see below), whose sum is σ = 3524385600. Its totient is φ = 414619200.

The previous prime is 1256317991. The next prime is 1256318033. The reversal of 1256317992 is 2997136521.

It is a happy number.

1256317992 is a `hidden beast` number, since 1 + 2 + 5 + 631 + 7 + 9 + 9 + 2 = 666.

It is not an unprimeable number, because it can be changed into a prime (1256317991) 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 15 ways as a sum of consecutive naturals, for example, 6978 + ... + 50609.

It is an arithmetic number, because the mean of its divisors is an integer number (55068525).

Almost surely, 2^1256317992 is an apocalyptic number.

1256317992 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 1256317992, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1762192800).

1256317992 is an abundant number, since it is smaller than the sum of its proper divisors (2268067608).

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

1256317992 is a wasteful number, since it uses less digits than its factorization.

1256317992 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 57703 (or 57693 counting only the distinct ones).

The product of its digits is 204120, while the sum is 45.

The square root of 1256317992 is about 35444.5763410991. The cubic root of 1256317992 is about 1079.0291893294.

The spelling of 1256317992 in words is "one billion, two hundred fifty-six million, three hundred seventeen thousand, nine hundred ninety-two".