30728056128 has 448 divisors, whose sum is σ = 107601715200. Its totient is φ = 7497308160.

The previous prime is 30728056091. The next prime is 30728056141. The reversal of 30728056128 is 82165082703.

It is a tau number, because it is divible by the number of its divisors (448).

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 30728056128.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 39044151 + ... + 39044937.

It is an arithmetic number, because the mean of its divisors is an integer number (240182400).

Almost surely, 2^30728056128 is an apocalyptic number.

30728056128 is a gapful number since it is divisible by the number (38) 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 30728056128, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (53800857600).

30728056128 is an abundant number, since it is smaller than the sum of its proper divisors (76873659072).

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

30728056128 is a wasteful number, since it uses less digits than its factorization.

30728056128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 978 (or 968 counting only the distinct ones).

The product of its (nonzero) digits is 161280, while the sum is 42.

The spelling of 30728056128 in words is "thirty billion, seven hundred twenty-eight million, fifty-six thousand, one hundred twenty-eight".