1256823040 has 144 divisors (see below), whose sum is σ = 3427837056. Its totient is φ = 437043200.

The previous prime is 1256823037. The next prime is 1256823041. The reversal of 1256823040 is 403286521.

It is a junction number, because it is equal to n+sod(n) for n = 1256822993 and 1256823011.

It is not an unprimeable number, because it can be changed into a prime (1256823041) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 321900 + ... + 325780.

It is an arithmetic number, because the mean of its divisors is an integer number (23804424).

Almost surely, 2^1256823040 is an apocalyptic number.

1256823040 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 1256823040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1713918528).

1256823040 is an abundant number, since it is smaller than the sum of its proper divisors (2171014016).

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

1256823040 is a wasteful number, since it uses less digits than its factorization.

1256823040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3936 (or 3922 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 31.

The square root of 1256823040 is about 35451.7001002773. The cubic root of 1256823040 is about 1079.1737622076.

The spelling of 1256823040 in words is "one billion, two hundred fifty-six million, eight hundred twenty-three thousand, forty".