128891428 has 48 divisors (see below), whose sum is σ = 244661760. Its totient is φ = 59270400.

The previous prime is 128891417. The next prime is 128891429. The reversal of 128891428 is 824198821.

It is a super-2 number, since 2×128891428² = 33226000423758368, which contains 22 as substring.

It is a Smith number, since the sum of its digits (43) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (128891429) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 262263 + ... + 262753.

It is an arithmetic number, because the mean of its divisors is an integer number (5097120).

Almost surely, 2^128891428 is an apocalyptic number.

It is an amenable number.

128891428 is a deficient number, since it is larger than the sum of its proper divisors (115770332).

128891428 is a wasteful number, since it uses less digits than its factorization.

128891428 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 628 (or 626 counting only the distinct ones).

The product of its digits is 73728, while the sum is 43.

The square root of 128891428 is about 11353.0360697040. The cubic root of 128891428 is about 505.1356404588.

The spelling of 128891428 in words is "one hundred twenty-eight million, eight hundred ninety-one thousand, four hundred twenty-eight".