30688128 has 96 divisors (see below), whose sum is σ = 93562560. Its totient is φ = 9621504.

The previous prime is 30688123. The next prime is 30688139. The reversal of 30688128 is 82188603.

It is a tau number, because it is divible by the number of its divisors (96).

It is a super-2 number, since 2×30688128² = 1883522400288768, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 30688092 and 30688101.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (30688121) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 18801 + ... + 20367.

It is an arithmetic number, because the mean of its divisors is an integer number (974610).

Almost surely, 2^30688128 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 30688128, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (46781280).

30688128 is an abundant number, since it is smaller than the sum of its proper divisors (62874432).

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

30688128 is a wasteful number, since it uses less digits than its factorization.

30688128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1604 (or 1589 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 36.

The square root of 30688128 is about 5539.6866337366. The cubic root of 30688128 is about 313.0810624762.

The spelling of 30688128 in words is "thirty million, six hundred eighty-eight thousand, one hundred twenty-eight".