128861616 has 80 divisors (see below), whose sum is σ = 370913760. Its totient is φ = 38277120.

The previous prime is 128861609. The next prime is 128861641. The reversal of 128861616 is 616168821.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a nude number because it is divisible by every one of its digits.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 14536 + ... + 21656.

It is an arithmetic number, because the mean of its divisors is an integer number (4636422).

Almost surely, 2^128861616 is an apocalyptic number.

128861616 is a gapful number since it is divisible by the number (16) 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 128861616, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (185456880).

128861616 is an abundant number, since it is smaller than the sum of its proper divisors (242052144).

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

128861616 is a wasteful number, since it uses less digits than its factorization.

128861616 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7174 (or 7168 counting only the distinct ones).

The product of its digits is 27648, while the sum is 39.

The square root of 128861616 is about 11351.7230410189. The cubic root of 128861616 is about 505.0966922652.

The spelling of 128861616 in words is "one hundred twenty-eight million, eight hundred sixty-one thousand, six hundred sixteen".