77928 has 32 divisors (see below), whose sum is σ = 207360. Its totient is φ = 24320.

The previous prime is 77899. The next prime is 77929. The reversal of 77928 is 82977.

It is not an unprimeable number, because it can be changed into a prime (77929) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 313 + ... + 503.

It is an arithmetic number, because the mean of its divisors is an integer number (6480).

2⁷⁷⁹²⁸ 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 77928, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (103680).

77928 is an abundant number, since it is smaller than the sum of its proper divisors (129432).

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

77928 is a wasteful number, since it uses less digits than its factorization.

77928 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 217 (or 213 counting only the distinct ones).

The product of its digits is 7056, while the sum is 33.

The square root of 77928 is about 279.1558704380. The cubic root of 77928 is about 42.7134361277.

It can be divided in two parts, 779 and 28, that multiplied together give a palindrome (21812).

The spelling of 77928 in words is "seventy-seven thousand, nine hundred twenty-eight".