78128 has 20 divisors (see below), whose sum is σ = 159960. Its totient is φ = 36864.

The previous prime is 78121. The next prime is 78137. The reversal of 78128 is 82187.

It is a super-2 number, since 2×78128² = 12207968768, which contains 22 as substring.

It is a hoax number, since the sum of its digits (26) coincides with the sum of the digits of its distinct prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 78097 and 78106.

It is not an unprimeable number, because it can be changed into a prime (78121) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 176 + ... + 432.

It is an arithmetic number, because the mean of its divisors is an integer number (7998).

2⁷⁸¹²⁸ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 78128, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (79980).

78128 is an abundant number, since it is smaller than the sum of its proper divisors (81832).

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

78128 is a wasteful number, since it uses less digits than its factorization.

78128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 284 (or 278 counting only the distinct ones).

The product of its digits is 896, while the sum is 26.

The square root of 78128 is about 279.5138636991. The cubic root of 78128 is about 42.7499458522.

The spelling of 78128 in words is "seventy-eight thousand, one hundred twenty-eight".