1256423040 has 192 divisors, whose sum is σ = 4358296800. Its totient is φ = 333527040.

The previous prime is 1256423033. The next prime is 1256423083. The reversal of 1256423040 is 403246521.

1256423040 is a `hidden beast` number, since 12 + 5 + 642 + 3 + 0 + 4 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (192).

It is a junction number, because it is equal to n+sod(n) for n = 1256422995 and 1256423013.

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, 1906231 + ... + 1906889.

Almost surely, 2^1256423040 is an apocalyptic number.

1256423040 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 1256423040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2179148400).

1256423040 is an abundant number, since it is smaller than the sum of its proper divisors (3101873760).

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

1256423040 is a wasteful number, since it uses less digits than its factorization.

1256423040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1015 (or 1000 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 27.

The square root of 1256423040 is about 35446.0581729478. The cubic root of 1256423040 is about 1079.0592631111.

Adding to 1256423040 its reverse (403246521), we get a palindrome (1659669561).

The spelling of 1256423040 in words is "one billion, two hundred fifty-six million, four hundred twenty-three thousand, forty".