128436784 has 80 divisors (see below), whose sum is σ = 301266432. Its totient is φ = 51853824.

The previous prime is 128436767. The next prime is 128436787. The reversal of 128436784 is 487634821.

It is a self number, because there is not a number n which added to its sum of digits gives 128436784.

It is not an unprimeable number, because it can be changed into a prime (128436787) 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, 187707 + ... + 188389.

Almost surely, 2^128436784 is an apocalyptic number.

128436784 is a gapful number since it is divisible by the number (14) 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 128436784, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (150633216).

128436784 is an abundant number, since it is smaller than the sum of its proper divisors (172829648).

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

128436784 is a wasteful number, since it uses less digits than its factorization.

128436784 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 794 (or 788 counting only the distinct ones).

The product of its digits is 258048, while the sum is 43.

The square root of 128436784 is about 11332.9953675099. The cubic root of 128436784 is about 504.5410122302.

The spelling of 128436784 in words is "one hundred twenty-eight million, four hundred thirty-six thousand, seven hundred eighty-four".