1556233728 has 480 divisors, whose sum is σ = 5373941760. Its totient is φ = 397393920.

The previous prime is 1556233717. The next prime is 1556233729. The reversal of 1556233728 is 8273326551.

It is a happy number.

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

It is a self number, because there is not a number n which added to its sum of digits gives 1556233728.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1556233729) 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, 50201073 + ... + 50201103.

It is an arithmetic number, because the mean of its divisors is an integer number (11195712).

Almost surely, 2^1556233728 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1556233728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2686970880).

1556233728 is an abundant number, since it is smaller than the sum of its proper divisors (3817708032).

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

1556233728 is a wasteful number, since it uses less digits than its factorization.

1556233728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 118 (or 95 counting only the distinct ones).

The product of its digits is 302400, while the sum is 42.

The square root of 1556233728 is about 39449.1283553896. The cubic root of 1556233728 is about 1158.8439056522.

The spelling of 1556233728 in words is "one billion, five hundred fifty-six million, two hundred thirty-three thousand, seven hundred twenty-eight".