128784816 has 50 divisors (see below), whose sum is σ = 372744372. Its totient is φ = 42927840.

The previous prime is 128784811. The next prime is 128784823. The reversal of 128784816 is 618487821.

It is not an unprimeable number, because it can be changed into a prime (128784811) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 48390 + ... + 50981.

Almost surely, 2^128784816 is an apocalyptic number.

128784816 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

128784816 is an abundant number, since it is smaller than the sum of its proper divisors (243959556).

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

128784816 is an equidigital number, since it uses as much as digits as its factorization.

128784816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 99391 (or 99376 counting only the distinct ones).

The product of its digits is 172032, while the sum is 45.

The square root of 128784816 is about 11348.3397904716. The cubic root of 128784816 is about 504.9963284378.

It can be divided in two parts, 128784 and 816, that added together give a square (129600 = 360²).

The spelling of 128784816 in words is "one hundred twenty-eight million, seven hundred eighty-four thousand, eight hundred sixteen".