1243568256 has 384 divisors, whose sum is σ = 4144219200. Its totient is φ = 328753152.

The previous prime is 1243568251. The next prime is 1243568267. The reversal of 1243568256 is 6528653421.

It is a tau number, because it is divible by the number of its divisors (384).

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1243568251) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 23463526 + ... + 23463578.

Almost surely, 2^1243568256 is an apocalyptic number.

1243568256 is a gapful number since it is divisible by the number (16) 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 1243568256, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2072109600).

1243568256 is an abundant number, since it is smaller than the sum of its proper divisors (2900650944).

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

1243568256 is a wasteful number, since it uses less digits than its factorization.

1243568256 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 156 (or 137 counting only the distinct ones).

The product of its digits is 345600, while the sum is 42.

The square root of 1243568256 is about 35264.2631569128. The cubic root of 1243568256 is about 1075.3665974490.

The spelling of 1243568256 in words is "one billion, two hundred forty-three million, five hundred sixty-eight thousand, two hundred fifty-six".