1256313322440 has 384 divisors, whose sum is σ = 4580546630400. Its totient is φ = 295943362560.

The previous prime is 1256313322393. The next prime is 1256313322483. The reversal of 1256313322440 is 442233136521.

1256313322440 is a `hidden beast` number, since 1 + 2 + 5 + 63 + 133 + 22 + 440 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 1256313322395 and 1256313322404.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 121459909 + ... + 121470251.

It is an arithmetic number, because the mean of its divisors is an integer number (11928506850).

Almost surely, 2^{1256313322440} is an apocalyptic number.

1256313322440 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 1256313322440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2290273315200).

1256313322440 is an abundant number, since it is smaller than the sum of its proper divisors (3324233307960).

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

1256313322440 is a wasteful number, since it uses less digits than its factorization.

1256313322440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11237 (or 11230 counting only the distinct ones).

The product of its (nonzero) digits is 103680, while the sum is 36.

Adding to 1256313322440 its reverse (442233136521), we get a palindrome (1698546458961).

The spelling of 1256313322440 in words is "one trillion, two hundred fifty-six billion, three hundred thirteen million, three hundred twenty-two thousand, four hundred forty".