777728 has 60 divisors (see below), whose sum is σ = 1865952. Its totient is φ = 322560.

The previous prime is 777683. The next prime is 777731. The reversal of 777728 is 827777.

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

It is a junction number, because it is equal to n+sod(n) for n = 777691 and 777700.

It is a congruent number.

It is an unprimeable number.

777728 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 25073 + ... + 25103.

2⁷⁷⁷⁷²⁸ 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 777728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (932976).

777728 is an abundant number, since it is smaller than the sum of its proper divisors (1088224).

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

777728 is an equidigital number, since it uses as much as digits as its factorization.

777728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 63 (or 40 counting only the distinct ones).

The product of its digits is 38416, while the sum is 38.

The square root of 777728 is about 881.8888818893. Note that the first 5 decimals coincide. The cubic root of 777728 is about 91.9621772692.

The spelling of 777728 in words is "seven hundred seventy-seven thousand, seven hundred twenty-eight".