1225888728 has 64 divisors (see below), whose sum is σ = 3152079360. Its totient is φ = 397128576.

The previous prime is 1225888723. The next prime is 1225888771. The reversal of 1225888728 is 8278885221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1225888723) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 131601 + ... + 140607.

It is an arithmetic number, because the mean of its divisors is an integer number (49251240).

Almost surely, 2^1225888728 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 1225888728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1576039680).

1225888728 is an abundant number, since it is smaller than the sum of its proper divisors (1926190632).

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

1225888728 is a wasteful number, since it uses less digits than its factorization.

1225888728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9176 (or 9172 counting only the distinct ones).

The product of its digits is 1146880, while the sum is 51.

The square root of 1225888728 is about 35012.6938123875. The cubic root of 1225888728 is about 1070.2461738883.

The spelling of 1225888728 in words is "one billion, two hundred twenty-five million, eight hundred eighty-eight thousand, seven hundred twenty-eight".