428365728 has 288 divisors, whose sum is σ = 1528450560. Its totient is φ = 110960640.

The previous prime is 428365727. The next prime is 428365759. The reversal of 428365728 is 827563824.

428365728 is a `hidden beast` number, since 42 + 8 + 36 + 572 + 8 = 666.

It is a tau number, because it is divible by the number of its divisors (288).

It is not an unprimeable number, because it can be changed into a prime (428365723) 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, 993673 + ... + 994103.

It is an arithmetic number, because the mean of its divisors is an integer number (5307120).

Almost surely, 2^428365728 is an apocalyptic number.

428365728 is a gapful number since it is divisible by the number (48) 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 428365728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (764225280).

428365728 is an abundant number, since it is smaller than the sum of its proper divisors (1100084832).

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

428365728 is a wasteful number, since it uses less digits than its factorization.

428365728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 500 (or 489 counting only the distinct ones).

The product of its digits is 645120, while the sum is 45.

The square root of 428365728 is about 20696.9980431946. The cubic root of 428365728 is about 753.8267982771.

The spelling of 428365728 in words is "four hundred twenty-eight million, three hundred sixty-five thousand, seven hundred twenty-eight".