128523728 has 20 divisors (see below), whose sum is σ = 253714788. Its totient is φ = 63048960.

The previous prime is 128523713. The next prime is 128523763. The reversal of 128523728 is 827325821.

It can be written as a sum of positive squares in 2 ways, for example, as 100560784 + 27962944 = 10028^2 + 5288^2 .

It is a junction number, because it is equal to n+sod(n) for n = 128523691 and 128523700.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 74933 + ... + 76628.

Almost surely, 2^128523728 is an apocalyptic number.

It is an amenable number.

128523728 is a deficient number, since it is larger than the sum of its proper divisors (125191060).

128523728 is a wasteful number, since it uses less digits than its factorization.

128523728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 151622 (or 151616 counting only the distinct ones).

The product of its digits is 53760, while the sum is 38.

The square root of 128523728 is about 11336.8305976582. The cubic root of 128523728 is about 504.6548345525.

The spelling of 128523728 in words is "one hundred twenty-eight million, five hundred twenty-three thousand, seven hundred twenty-eight".